diff --git a/store/src/main/java/org/apache/rocketmq/store/index/IndexService.java b/store/src/main/java/org/apache/rocketmq/store/index/IndexService.java
index 1a180e4442b..35e05864c25 100644
--- a/store/src/main/java/org/apache/rocketmq/store/index/IndexService.java
+++ b/store/src/main/java/org/apache/rocketmq/store/index/IndexService.java
@@ -173,7 +173,10 @@ public QueryOffsetResult queryOffset(String topic, String key, int maxNum, long
     public QueryOffsetResult queryOffset(String topic, String key, int maxNum, long begin, long end, String indexType) {
         long indexLastUpdateTimestamp = 0;
         long indexLastUpdatePhyoffset = 0;
-        maxNum = Math.min(maxNum, this.defaultMessageStore.getMessageStoreConfig().getMaxMsgsNumBatch());
+        // maxNum comes from the request header and is only checked for null,
+        // so a negative value must be clamped here instead of blowing up the
+        // ArrayList allocation below with an IllegalArgumentException.
+        maxNum = Math.min(Math.max(maxNum, 0), this.defaultMessageStore.getMessageStoreConfig().getMaxMsgsNumBatch());
         List<Long> phyOffsets = new ArrayList<>(maxNum);
         try {
             this.readWriteLock.readLock().lock();
diff --git a/store/src/test/java/org/apache/rocketmq/store/index/IndexServiceTest.java b/store/src/test/java/org/apache/rocketmq/store/index/IndexServiceTest.java
index bd520e6a483..982dd2296db 100644
--- a/store/src/test/java/org/apache/rocketmq/store/index/IndexServiceTest.java
+++ b/store/src/test/java/org/apache/rocketmq/store/index/IndexServiceTest.java
@@ -81,4 +81,11 @@ public void testQueryOffsetWithZeroMaxNum() {
         assertNotNull(result);
         assertEquals(Collections.emptyList(), result.getPhyOffsets());
     }
+
+    @Test
+    public void testQueryOffsetWithNegativeMaxNum() {
+        QueryOffsetResult result = indexService.queryOffset("test", "testKey", -1, 0, 100);
+        assertNotNull(result);
+        assertEquals(Collections.emptyList(), result.getPhyOffsets());
+    }
 }