diff --git a/eng/RuntimeIdentifier.props b/eng/RuntimeIdentifier.props
index a3c396d8e6b6c7..86a42ce61f074c 100644
--- a/eng/RuntimeIdentifier.props
+++ b/eng/RuntimeIdentifier.props
@@ -19,6 +19,7 @@
     <!-- Detect linux flavors using __PortableTargetOS from the native script. -->
     <PortableOS Condition="'$(PortableOS)' == 'linux' and '$(__PortableTargetOS)' == 'linux-musl'">linux-musl</PortableOS>
     <PortableOS Condition="'$(PortableOS)' == 'linux' and '$(__PortableTargetOS)' == 'linux-bionic'">linux-bionic</PortableOS>
+    <PortableOS Condition="'$(PortableOS)' == 'linux' and '$(__PortableTargetOS)' == 'linux-ohos'">linux-ohos</PortableOS>
 
     <PortableTargetRid Condition="'$(PortableTargetRid)' == ''">$(PortableOS)-$(TargetArchitecture)</PortableTargetRid>
   </PropertyGroup>
@@ -50,7 +51,8 @@
     <TargetsLinux Condition="'$(TargetOS)' == 'linux' or '$(TargetOS)' == 'android'">true</TargetsLinux>
     <TargetsLinuxBionic Condition="'$(PortableOS)' == 'linux-bionic'">true</TargetsLinuxBionic>
     <TargetsLinuxMusl Condition="'$(PortableOS)' == 'linux-musl'">true</TargetsLinuxMusl>
-    <TargetsLinuxGlibc Condition="'$(TargetsLinux)' == 'true' and '$(TargetsLinuxMusl)' != 'true' and '$(TargetsLinuxBionic)' != 'true'">true</TargetsLinuxGlibc>
+    <TargetOpenHarmony Condition="'$(PortableOS)' == 'linux-ohos'">true</TargetOpenHarmony>
+    <TargetsLinuxGlibc Condition="'$(TargetsLinux)' == 'true' and '$(TargetsLinuxMusl)' != 'true' and '$(TargetsLinuxBionic)' != 'true' and '$(TargetOpenHarmony)' != 'true'">true</TargetsLinuxGlibc>
     <TargetsNetBSD Condition="'$(TargetOS)' == 'netbsd'">true</TargetsNetBSD>
     <TargetsOSX Condition="'$(TargetOS)' == 'osx'">true</TargetsOSX>
     <TargetsMacCatalyst Condition="'$(TargetOS)' == 'maccatalyst'">true</TargetsMacCatalyst>
diff --git a/eng/Subsets.props b/eng/Subsets.props
index d7b4c953cd9f73..9f320412de2f65 100644
--- a/eng/Subsets.props
+++ b/eng/Subsets.props
@@ -56,7 +56,7 @@
     <SdkToolsSupported Condition="'$(_SdkToolsSupportedOS)' == 'true' and '$(_SdkToolsSupportedArch)' == 'true'">true</SdkToolsSupported>
 
     <_UseNativeAotForComponentsCrossOS Condition="'$(CrossBuild)' == 'true' and '$(_hostArchitecture)' == '$(_targetArchitecture)' and '$(_hostOS)' != 'windows'">true</_UseNativeAotForComponentsCrossOS>
-    <UseNativeAotForComponents Condition="'$(NativeAotSupported)' == 'true' and ('$(TargetOS)' == '$(HostOS)' or '$(_UseNativeAotForComponentsCrossOS)' == 'true') and '$(TargetsLinuxBionic)' != 'true'">true</UseNativeAotForComponents>
+    <UseNativeAotForComponents Condition="'$(NativeAotSupported)' == 'true' and ('$(TargetOS)' == '$(HostOS)' or '$(_UseNativeAotForComponentsCrossOS)' == 'true') and '$(TargetsLinuxBionic)' != 'true' and '$(TargetOpenHarmony)' != 'true'">true</UseNativeAotForComponents>
   </PropertyGroup>
 
   <PropertyGroup>
@@ -77,6 +77,9 @@
     <DefaultSubsets Condition="'$(TargetsLinuxBionic)' == 'true' and '$(CoreCLRSupported)' == 'true' and '$(MonoSupported)' != 'true'">clr+libs+host+packs</DefaultSubsets>
     <DefaultSubsets Condition="'$(TargetsLinuxBionic)' == 'true' and '$(CoreCLRSupported)' != 'true' and '$(MonoSupported)' == 'true'">clr.nativeaotruntime+clr.nativeaotlibs+mono+libs+host+packs</DefaultSubsets>
     <DefaultSubsets Condition="'$(TargetsLinuxBionic)' == 'true' and '$(CoreCLRSupported)' != 'true' and '$(MonoSupported)' != 'true'">clr.nativeaotruntime+clr.nativeaotlibs+libs+packs</DefaultSubsets>
+    <DefaultSubsets Condition="'$(TargetOpenHarmony)' == 'true' and '$(CoreCLRSupported)' == 'true' and '$(MonoSupported)' == 'true'">clr.nativeaotruntime+clr.nativeaotlibs+clr+mono+libs+host+packs</DefaultSubsets>
+    <DefaultSubsets Condition="'$(TargetOpenHarmony)' == 'true' and '$(CoreCLRSupported)' == 'true' and '$(MonoSupported)' != 'true'">clr.nativeaotruntime+clr.nativeaotlibs+clr+libs+host+packs</DefaultSubsets>
+    <DefaultSubsets Condition="'$(TargetOpenHarmony)' == 'true' and '$(CoreCLRSupported)' != 'true'">clr.nativeaotruntime+clr.nativeaotlibs+mono+libs+host+packs</DefaultSubsets>
     <DefaultSubsets Condition="'$(TargetsBrowser)' == 'true' and '$(RuntimeFlavor)' == 'CoreCLR'">clr+libs+tools+host+packs</DefaultSubsets>
     <!-- In source build, mono is only supported as primary runtime flavor. -->
     <DefaultSubsets Condition="'$(DotNetBuildSourceOnly)' == 'true' and '$(PrimaryRuntimeFlavor)' != 'Mono'">clr+libs+tools+host+packs</DefaultSubsets>
@@ -384,8 +387,9 @@
     -->
   <PropertyGroup>
     <!-- linux-bionic reports TargetOS as 'linux', so the HostOS/TargetOS check below never fires for it.
-         It always targets the bionic libc via the NDK though, so host tools must be built separately. -->
-    <_BuildAnyCrossArch Condition="('$(CrossBuild)' == 'true' or '$(BuildArchitecture)' != '$(TargetArchitecture)' or '$(HostOS)' != '$(TargetOS)' or '$(TargetsLinuxBionic)' == 'true' or '$(EnableNativeSanitizers)' != '')">true</_BuildAnyCrossArch>
+         It always targets the bionic libc via the NDK though, so host tools must be built separately.
+         linux-ohos (HarmonyOS) similarly reports TargetOS as 'linux' and uses its own NDK toolchain. -->
+    <_BuildAnyCrossArch Condition="('$(CrossBuild)' == 'true' or '$(BuildArchitecture)' != '$(TargetArchitecture)' or '$(HostOS)' != '$(TargetOS)' or '$(TargetsLinuxBionic)' == 'true' or '$(TargetOpenHarmony)' == 'true' or '$(EnableNativeSanitizers)' != '')">true</_BuildAnyCrossArch>
     <_BuildCrossComponents Condition="$(_subset.Contains('+clr.crossarchtools+'))">true</_BuildCrossComponents>
     <_BuildCrossComponents Condition="'$(ClrRuntimeBuildSubsets)' != '' and ('$(PrimaryRuntimeFlavor)' == 'CoreCLR' or '$(TargetsMobile)' == 'true')">true</_BuildCrossComponents>
     <_CrossBitwidthBuild Condition="'$(BuildArchitecture)' == 'x64' and ('$(TargetArchitecture)' == 'x86' or '$(TargetArchitecture)' == 'arm')">true</_CrossBitwidthBuild>
diff --git a/eng/build.sh b/eng/build.sh
index b4496e0bc362f1..c21ae714389875 100755
--- a/eng/build.sh
+++ b/eng/build.sh
@@ -32,7 +32,7 @@ usage()
   echo "                                  [Default: Debug]"
   echo "  --os                            Target operating system: windows, linux, freebsd, osx, maccatalyst, tvos,"
   echo "                                  tvossimulator, ios, iossimulator, android, browser, wasi, netbsd, illumos, solaris"
-  echo "                                  linux-musl, linux-bionic, tizen, or haiku."
+  echo "                                  linux-musl, linux-bionic, linux-ohos, tizen, or haiku."
   echo "                                  [Default: Your machine's OS.]"
   echo "  --targetrid <rid>               Optional argument that overrides the target rid name."
   echo "  --projects <value>              Project or solution file(s) to build."
@@ -146,8 +146,9 @@ initDistroRid()
     local isCrossBuild="$3"
 
     # Only pass ROOTFS_DIR if __DoCrossArchBuild is specified and the current platform is not an Apple platform (that doesn't use rootfs)
-    if [[ $isCrossBuild == 1 && "$targetOs" != "osx" && "$targetOs" != "android" && "$targetOs" != "ios" && "$targetOs" != "iossimulator" && "$targetOs" != "tvos" && "$targetOs" != "tvossimulator" && "$targetOs" != "maccatalyst" ]]; then
-        passedRootfsDir=${ROOTFS_DIR}
+    # HarmonyOS uses its NDK toolchain, so no rootfs is required either.
+    if [[ $isCrossBuild == 1 && "$targetOs" != "osx" && "$targetOs" != "android" && "$targetOs" != "ios" && "$targetOs" != "iossimulator" && "$targetOs" != "tvos" && "$targetOs" != "tvossimulator" && "$targetOs" != "maccatalyst" && "${__PortableTargetOS:-}" != "linux-ohos" ]]; then
+        passedRootfsDir=${ROOTFS_DIR:-}
     fi
     initDistroRidGlobal "${targetOs}" "${targetArch}" "${passedRootfsDir}"
 }
@@ -310,6 +311,10 @@ while [[ $# -gt 0 ]]; do
           os="linux"
           __PortableTargetOS=linux-musl
           ;;
+        linux-ohos)
+          os="linux"
+          __PortableTargetOS=linux-ohos
+          ;;
         haiku)
           os="haiku" ;;
         *)
diff --git a/eng/liveBuilds.targets b/eng/liveBuilds.targets
index e494ca933bdbea..b56886ca5e8569 100644
--- a/eng/liveBuilds.targets
+++ b/eng/liveBuilds.targets
@@ -15,6 +15,7 @@
   <!-- Set up default live asset paths if no overrides provided. -->
   <PropertyGroup>
     <CoreCLRArtifactsPath Condition="'$(CoreCLRArtifactsPath)' == ''">$([MSBuild]::NormalizeDirectory('$(RepoRoot)', 'artifacts', 'bin', 'coreclr', '$(TargetOS).$(TargetArchitecture).$(CoreCLRConfiguration)'))</CoreCLRArtifactsPath>
+    <CoreCLRArtifactsPath Condition="'$(TargetOpenHarmony)' == 'true'">$([MSBuild]::NormalizeDirectory('$(RepoRoot)', 'artifacts', 'bin', 'coreclr', 'linux-ohos.$(TargetArchitecture).$(CoreCLRConfiguration)'))</CoreCLRArtifactsPath>
     <MonoArtifactsPath Condition="'$(MonoArtifactsPath)' == ''">$([MSBuild]::NormalizeDirectory('$(RepoRoot)', 'artifacts', 'bin', 'mono', '$(TargetOS).$(TargetArchitecture).$(MonoConfiguration)'))</MonoArtifactsPath>
     <LibrariesArtifactsPath Condition="'$(LibrariesArtifactsPath)' == ''">$([MSBuild]::NormalizeDirectory('$(RepoRoot)', 'artifacts'))</LibrariesArtifactsPath>
     <LibrariesAllConfigurationsArtifactsPath Condition="'$(LibrariesAllConfigurationsArtifactsPath)' == ''">$([MSBuild]::NormalizeDirectory('$(RepoRoot)', 'artifacts'))</LibrariesAllConfigurationsArtifactsPath>
diff --git a/eng/native/build-commons.sh b/eng/native/build-commons.sh
index fdf156b16fec2e..6409a7efb16728 100755
--- a/eng/native/build-commons.sh
+++ b/eng/native/build-commons.sh
@@ -7,7 +7,7 @@ initTargetDistroRid()
     local passedRootfsDir=""
 
     # Only pass ROOTFS_DIR if cross is specified and the target platform is not Darwin that doesn't use rootfs
-    if [[ "$__CrossBuild" == 1 && "$platform" != "darwin" ]]; then
+    if [[ "$__CrossBuild" == 1 && "$platform" != "darwin" && "$__TargetOS" != "linux-ohos" ]]; then
         passedRootfsDir="$ROOTFS_DIR"
     fi
 
@@ -137,6 +137,38 @@ build_native()
             echo "Error: Unknown Android architecture $hostArch."
             exit 1
         fi
+    elif [[ "$targetOS" == linux-ohos ]]; then
+        # HarmonyOS (OpenHarmony) NDK-style toolchain. The OHOS NDK provides its
+        # own CMake toolchain file (ohos.toolchain.cmake) which sets CMAKE_SYSTEM_NAME=OHOS
+        # and selects the aarch64/arm/x86_64 linux-ohos clang wrappers + sysroot.
+        if [[ -z "$OHOS_NDK_HOME" ]]; then
+            echo "Error: You need to set the OHOS_NDK_HOME environment variable pointing to the HarmonyOS NDK root."
+            exit 1
+        fi
+
+        local ohosToolchainFile="$OHOS_NDK_HOME/native/build/cmake/ohos.toolchain.cmake"
+        if [[ ! -f "$ohosToolchainFile" ]]; then
+            echo "Error: OHOS CMake toolchain file not found at $ohosToolchainFile. Verify OHOS_NDK_HOME."
+            exit 1
+        fi
+
+        cmakeArgs="-DCMAKE_TOOLCHAIN_FILE=$ohosToolchainFile $cmakeArgs"
+        cmakeArgs="-DOHOS_NDK_HOME=$OHOS_NDK_HOME $cmakeArgs"
+        cmakeArgs="-C $__RepoRootDir/eng/native/tryrun.cmake $cmakeArgs"
+
+        # Don't try to set CC/CXX in init-compiler.sh - it's handled in ohos.toolchain.cmake already
+        __Compiler="default"
+
+        if [[ "$hostArch" == arm64 ]]; then
+            cmakeArgs="-DOHOS_ARCH=arm64-v8a $cmakeArgs"
+        elif [[ "$hostArch" == arm ]]; then
+            cmakeArgs="-DOHOS_ARCH=armeabi-v7a $cmakeArgs"
+        elif [[ "$hostArch" == x64 ]]; then
+            cmakeArgs="-DOHOS_ARCH=x86_64 $cmakeArgs"
+        else
+            echo "Error: Unknown OHOS architecture $hostArch."
+            exit 1
+        fi
     elif [[ "$targetOS" == iossimulator ]]; then
         cmakeArgs="-C $__RepoRootDir/eng/native/tryrun_ios_tvos.cmake $cmakeArgs"
 
@@ -596,6 +628,9 @@ elif [[ "$__TargetOS" == osx || "$__TargetOS" == maccatalyst ]]; then
 elif [[ "$__TargetOS" == android ]]; then
     # nothing to do here
     true
+elif [[ "$__TargetOS" == linux-ohos ]]; then
+    # HarmonyOS uses its NDK toolchain, no rootfs required
+    true
 else
     __CMakeArgs="-DFEATURE_DISTRO_AGNOSTIC_SSL=$__PortableBuild $__CMakeArgs"
 fi
@@ -604,8 +639,8 @@ fi
 if [[ "$__CrossBuild" == 1 ]]; then
     CROSSCOMPILE=1
     export CROSSCOMPILE
-    # Darwin that doesn't use rootfs
-    if [[ -z "$ROOTFS_DIR" && "$platform" != "darwin" ]]; then
+    # Darwin that doesn't use rootfs; HarmonyOS uses its NDK toolchain
+    if [[ -z "$ROOTFS_DIR" && "$platform" != "darwin" && "$__TargetOS" != "linux-ohos" ]]; then
         ROOTFS_DIR="$__RepoRootDir/.tools/rootfs/$__TargetArch"
         export ROOTFS_DIR
     fi
diff --git a/eng/native/configurecompiler.cmake b/eng/native/configurecompiler.cmake
index bc5fcb1733acb7..55b1bfb309afbf 100644
--- a/eng/native/configurecompiler.cmake
+++ b/eng/native/configurecompiler.cmake
@@ -653,6 +653,20 @@ if (CLR_CMAKE_HOST_UNIX OR CLR_CMAKE_HOST_WASI)
     add_compile_options(-fstack-protector-strong)
   endif()
 
+  if(CLR_CMAKE_HOST_OPENHARMONY)
+    # The OHOS NDK toolchain injects --gcc-toolchain (via CMAKE_C_COMPILER_EXTERNAL_TOOLCHAIN)
+    # which clang reports as unused; silence it (in CMAKE_C_FLAGS so try_compile checks
+    # inherit it) so -Werror doesn't fail the build. Applies to assembly too.
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Qunused-arguments")
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Qunused-arguments")
+    set(CMAKE_ASM_FLAGS "${CMAKE_ASM_FLAGS} -Qunused-arguments")
+    # The arm64 asm helpers access t_ThreadStatics/t_runtime_thread_locals via TLS
+    # descriptors; the C++ definitions must use native (non-emulated) TLS with the
+    # global-dynamic model to match.
+    add_compile_options(-fno-emulated-tls)
+    add_compile_options(-ftls-model=global-dynamic)
+  endif()
+
   # Suppress warnings-as-errors in release branches to reduce servicing churn
   if (PRERELEASE)
     add_compile_options(-Werror)
@@ -845,6 +859,9 @@ if(CLR_CMAKE_TARGET_UNIX)
     if(CLR_CMAKE_TARGET_LINUX_MUSL)
         add_compile_definitions($<$<NOT:$<BOOL:$<TARGET_PROPERTY:IGNORE_DEFAULT_TARGET_OS>>>:TARGET_LINUX_MUSL>)
     endif()
+    if(CLR_CMAKE_TARGET_OPENHARMONY)
+      add_compile_definitions($<$<NOT:$<BOOL:$<TARGET_PROPERTY:IGNORE_DEFAULT_TARGET_OS>>>:TARGET_OPENHARMONY>)
+    endif()
     if(CLR_CMAKE_TARGET_ANDROID)
       add_compile_definitions($<$<NOT:$<BOOL:$<TARGET_PROPERTY:IGNORE_DEFAULT_TARGET_OS>>>:TARGET_ANDROID>)
     endif()
diff --git a/eng/native/configureplatform.cmake b/eng/native/configureplatform.cmake
index 2ccced093f6b38..f04fba710b8cae 100644
--- a/eng/native/configureplatform.cmake
+++ b/eng/native/configureplatform.cmake
@@ -11,6 +11,13 @@ set(PRERELEASE 1)
 #----------------------------------------
 set(CLR_CMAKE_HOST_OS ${CMAKE_SYSTEM_NAME})
 string(TOLOWER ${CLR_CMAKE_HOST_OS} CLR_CMAKE_HOST_OS)
+# HarmonyOS (OpenHarmony) uses the OHOS NDK CMake toolchain which sets
+# CMAKE_SYSTEM_NAME=OHOS. Its libc is musl-based, so treat it as a linux/musl target.
+if(CLR_CMAKE_HOST_OS STREQUAL ohos)
+    set(CLR_CMAKE_HOST_OS linux)
+    set(CLR_CMAKE_HOST_LINUX_MUSL 1)
+    set(CLR_CMAKE_HOST_OPENHARMONY 1)
+endif()
 if(CLR_CMAKE_HOST_OS STREQUAL linux)
     set(CLR_CMAKE_HOST_UNIX 1)
     if(CLR_CROSS_COMPONENTS_BUILD)
@@ -357,6 +364,10 @@ if(CLR_CMAKE_HOST_LINUX_MUSL OR CLR_CMAKE_TARGET_OS STREQUAL alpine)
     set(CLR_CMAKE_TARGET_LINUX_MUSL 1)
 endif(CLR_CMAKE_HOST_LINUX_MUSL OR CLR_CMAKE_TARGET_OS STREQUAL alpine)
 
+if(CLR_CMAKE_HOST_OPENHARMONY)
+    set(CLR_CMAKE_TARGET_OPENHARMONY 1)
+endif()
+
 macro(set_cache_value)
   set(${ARGV0} ${ARGV1} CACHE STRING "Result from TRY_RUN" FORCE)
   set(${ARGV0}__TRYRUN_OUTPUT "dummy output" CACHE STRING "Output from TRY_RUN" FORCE)
diff --git a/eng/native/configuretools.cmake b/eng/native/configuretools.cmake
index 16d039acc39830..6d3fa2c59799d5 100644
--- a/eng/native/configuretools.cmake
+++ b/eng/native/configuretools.cmake
@@ -28,11 +28,27 @@ if(NOT WIN32 AND NOT CLR_CMAKE_TARGET_BROWSER AND NOT CLR_CMAKE_TARGET_WASI)
       return()
     endif()
 
+    # For NDK-style toolchains (HarmonyOS) the compiler lives outside PATH.
+    # Hint find_program at the compiler's directory so tools like llvm-ar/nm are located.
+    # Guarded to OHOS only so other platforms keep their existing lookup behavior.
+    if(CLR_CMAKE_HOST_OPENHARMONY)
+      get_filename_component(CLR_COMPILER_DIR "${CMAKE_C_COMPILER}" DIRECTORY)
+    endif()
+
     unset(EXEC_LOCATION_${exec} CACHE)
-    find_program(EXEC_LOCATION_${exec}
-      NAMES
-      "${TOOLSET_PREFIX}${exec}${CLR_CMAKE_COMPILER_FILE_NAME_VERSION}"
-      "${TOOLSET_PREFIX}${exec}")
+    if(CLR_CMAKE_HOST_OPENHARMONY)
+      find_program(EXEC_LOCATION_${exec}
+        NAMES
+        "${TOOLSET_PREFIX}${exec}${CLR_CMAKE_COMPILER_FILE_NAME_VERSION}"
+        "${TOOLSET_PREFIX}${exec}"
+        HINTS
+        "${CLR_COMPILER_DIR}")
+    else()
+      find_program(EXEC_LOCATION_${exec}
+        NAMES
+        "${TOOLSET_PREFIX}${exec}${CLR_CMAKE_COMPILER_FILE_NAME_VERSION}"
+        "${TOOLSET_PREFIX}${exec}")
+    endif()
 
     if (required AND EXEC_LOCATION_${exec} STREQUAL "EXEC_LOCATION_${exec}-NOTFOUND")
       message(FATAL_ERROR "Unable to find toolchain executable. Name: '${exec}', Prefix: '${TOOLSET_PREFIX}'")
diff --git a/eng/native/gen-buildsys.sh b/eng/native/gen-buildsys.sh
index 72b82a136ce17d..63c005859df273 100755
--- a/eng/native/gen-buildsys.sh
+++ b/eng/native/gen-buildsys.sh
@@ -63,8 +63,8 @@ done
 cmake_extra_defines=
 if [[ "$CROSSCOMPILE" == "1" ]]; then
     platform="$(uname -s | tr '[:upper:]' '[:lower:]')"
-    # OSX doesn't use rootfs
-    if ! [[ -n "$ROOTFS_DIR" || "$platform" == "darwin" ]]; then
+    # OSX doesn't use rootfs; HarmonyOS uses its NDK toolchain
+    if ! [[ -n "$ROOTFS_DIR" || "$platform" == "darwin" || "$target_os" == "linux-ohos" ]]; then
         echo "ROOTFS_DIR not set for crosscompile"
         exit 1
     fi
@@ -76,6 +76,9 @@ if [[ "$CROSSCOMPILE" == "1" ]]; then
 
     if [[ "$platform" == "darwin" ]]; then
         cmake_extra_defines="$cmake_extra_defines -DCMAKE_SYSTEM_NAME=Darwin"
+    elif [[ "$target_os" == "linux-ohos" ]]; then
+        # HarmonyOS NDK toolchain is injected by build-commons.sh; do not override it.
+        true
     else
         cmake_extra_defines="$cmake_extra_defines -DCMAKE_TOOLCHAIN_FILE=$scriptroot/../common/cross/toolchain.cmake"
     fi
diff --git a/src/coreclr/clr.featuredefines.props b/src/coreclr/clr.featuredefines.props
index 9592c1919a8efa..f9ea77e08470a3 100644
--- a/src/coreclr/clr.featuredefines.props
+++ b/src/coreclr/clr.featuredefines.props
@@ -41,7 +41,7 @@
     </PropertyGroup>
 
     <PropertyGroup Condition="'$(TargetsUnix)' == 'true'">
-        <FeatureXplatEventSource Condition="'$(FeatureXplatEventSource)' == '' AND '$(TargetOS)' == 'linux'">true</FeatureXplatEventSource>
+        <FeatureXplatEventSource Condition="'$(FeatureXplatEventSource)' == '' AND '$(TargetOS)' == 'linux' AND '$(TargetOpenHarmony)' != 'true'">true</FeatureXplatEventSource>
         <FeatureComWrappers>true</FeatureComWrappers>
     </PropertyGroup>
 
diff --git a/src/coreclr/runtime.proj b/src/coreclr/runtime.proj
index b20e9a35fc87ab..8cfba3fe01f998 100644
--- a/src/coreclr/runtime.proj
+++ b/src/coreclr/runtime.proj
@@ -3,6 +3,7 @@
   <PropertyGroup>
     <_BuildNativeTargetOS>$(TargetOS)</_BuildNativeTargetOS>
     <_BuildNativeTargetOS Condition="'$(TargetsLinuxBionic)' == 'true'">linux-bionic</_BuildNativeTargetOS>
+    <_BuildNativeTargetOS Condition="'$(TargetOpenHarmony)' == 'true'">linux-ohos</_BuildNativeTargetOS>
     <HasCdacBuildTool Condition="'$(ClrFullNativeBuild)' == 'true' or '$(ClrRuntimeSubset)' == 'true' or '$(ClrDebugSubset)' == 'true' or '$(ClrCrossComponentsSubset)' == 'true' or '$(ClrNativeAotSubset)' == 'true'">true</HasCdacBuildTool>
     <BuildRuntimeDependsOnTargets>GetPgoDataPackagePath</BuildRuntimeDependsOnTargets>
     <BuildRuntimeDependsOnTargets Condition="'$(EnableSourceControlManagerQueries)' == 'true'">$(BuildRuntimeDependsOnTargets);InitializeSourceControlInformationFromSourceControlManager</BuildRuntimeDependsOnTargets>
diff --git a/src/native/corehost/corehost.proj b/src/native/corehost/corehost.proj
index 05a479acd8884b..118ecf080f422f 100644
--- a/src/native/corehost/corehost.proj
+++ b/src/native/corehost/corehost.proj
@@ -62,6 +62,7 @@
 
       <_CoreHostUnixTargetOS>$(TargetOS)</_CoreHostUnixTargetOS>
       <_CoreHostUnixTargetOS Condition="'$(TargetsLinuxBionic)' == 'true'">linux-bionic</_CoreHostUnixTargetOS>
+      <_CoreHostUnixTargetOS Condition="'$(TargetOpenHarmony)' == 'true'">linux-ohos</_CoreHostUnixTargetOS>
       <BuildArgs>$(Configuration) $(TargetArchitecture) -commithash "$([MSBuild]::ValueOrDefault('$(SourceRevisionId)', 'N/A'))" -os $(_CoreHostUnixTargetOS)</BuildArgs>
       <BuildArgs>$(BuildArgs) -cmakeargs "-DVERSION_FILE_PATH=$(NativeVersionFile)"</BuildArgs>
     </PropertyGroup>
diff --git a/src/native/libs/System.Native/CMakeLists.txt b/src/native/libs/System.Native/CMakeLists.txt
index 5930703021940b..8273eb07010019 100644
--- a/src/native/libs/System.Native/CMakeLists.txt
+++ b/src/native/libs/System.Native/CMakeLists.txt
@@ -57,7 +57,7 @@ else() # WASI
     )
 endif()
 
-if (CLR_CMAKE_TARGET_APPLE OR CLR_CMAKE_TARGET_ANDROID OR CLR_CMAKE_TARGET_BROWSER OR CLR_CMAKE_TARGET_WASI OR CLR_CMAKE_TARGET_OPENBSD OR CLR_CMAKE_TARGET_HAIKU)
+if (CLR_CMAKE_TARGET_APPLE OR CLR_CMAKE_TARGET_ANDROID OR CLR_CMAKE_TARGET_BROWSER OR CLR_CMAKE_TARGET_WASI OR CLR_CMAKE_TARGET_OPENBSD OR CLR_CMAKE_TARGET_HAIKU OR CLR_CMAKE_TARGET_OPENHARMONY)
     # These platforms do not support robust mutexes.
     # Keep an OS list instead of CMake configure checks since we also need to synchronize this with
     # the compile-time guards on the managed code side at
diff --git a/src/native/libs/build-native.proj b/src/native/libs/build-native.proj
index ac7308eb4e0f25..c202a1400572ac 100644
--- a/src/native/libs/build-native.proj
+++ b/src/native/libs/build-native.proj
@@ -9,6 +9,7 @@
     <AssemblyName>.NET Runtime</AssemblyName>
     <_BuildNativeTargetOS>$(TargetOS)</_BuildNativeTargetOS>
     <_BuildNativeTargetOS Condition="'$(TargetsLinuxBionic)' == 'true'">linux-bionic</_BuildNativeTargetOS>
+    <_BuildNativeTargetOS Condition="'$(TargetOpenHarmony)' == 'true'">linux-ohos</_BuildNativeTargetOS>
     <_BuildNativeOutConfig>$(NetCoreAppCurrent)-$(TargetOS)-$(Configuration)-$(TargetArchitecture)</_BuildNativeOutConfig>
     <_BuildNativeArgs>$(TargetArchitecture) $(Configuration) outconfig $(_BuildNativeOutConfig) -os $(_BuildNativeTargetOS)</_BuildNativeArgs>
     <_BuildNativeArgs Condition="'$(EnableNativeSanitizers)' != ''">$(_BuildNativeArgs) -fsanitize=$(EnableNativeSanitizers)</_BuildNativeArgs>
diff --git a/src/native/libs/build-native.sh b/src/native/libs/build-native.sh
index 05b77499d7d40a..a6e850daa5873b 100755
--- a/src/native/libs/build-native.sh
+++ b/src/native/libs/build-native.sh
@@ -58,7 +58,7 @@ else
     __CMakeArgs="-DFEATURE_DISTRO_AGNOSTIC_SSL=$__PortableBuild $__CMakeArgs"
     __CMakeArgs="-DCMAKE_STATIC_LIB_LINK=$__StaticLibLink $__CMakeArgs"
 
-    if [[ "$__TargetOS" != linux-bionic && "$__TargetArch" != x86 && "$__TargetArch" != x64 && "$__TargetArch" != "$__HostArch" ]]; then
+    if [[ "$__TargetOS" != linux-bionic && "$__TargetOS" != linux-ohos && "$__TargetArch" != x86 && "$__TargetArch" != x64 && "$__TargetArch" != "$__HostArch" ]]; then
         __CrossBuild=1
         echo "Set CrossBuild for $__TargetArch build"
     fi