diff --git a/seatunnel-formats/seatunnel-format-compatible-debezium-json/src/main/java/org/apache/seatunnel/format/compatible/debezium/json/CompatibleDebeziumJsonSerializationSchema.java b/seatunnel-formats/seatunnel-format-compatible-debezium-json/src/main/java/org/apache/seatunnel/format/compatible/debezium/json/CompatibleDebeziumJsonSerializationSchema.java
index 4d692663fee..b4b4f47cf5c 100644
--- a/seatunnel-formats/seatunnel-format-compatible-debezium-json/src/main/java/org/apache/seatunnel/format/compatible/debezium/json/CompatibleDebeziumJsonSerializationSchema.java
+++ b/seatunnel-formats/seatunnel-format-compatible-debezium-json/src/main/java/org/apache/seatunnel/format/compatible/debezium/json/CompatibleDebeziumJsonSerializationSchema.java
@@ -30,15 +30,20 @@
 @RequiredArgsConstructor
 public class CompatibleDebeziumJsonSerializationSchema implements SerializationSchema {
 
+    private final boolean isKey;
     private final int index;
 
     public CompatibleDebeziumJsonSerializationSchema(SeaTunnelRowType rowType, boolean isKey) {
+        this.isKey = isKey;
         this.index = rowType.indexOf(isKey ? FIELD_KEY : FIELD_VALUE);
     }
 
     @Override
     public byte[] serialize(SeaTunnelRow row) {
         String field = (String) row.getField(index);
+        if (isKey && field == null) {
+            return null;
+        }
         return field.getBytes();
     }
 }
diff --git a/seatunnel-formats/seatunnel-format-compatible-debezium-json/src/test/java/org/apache/seatunnel/format/compatible/debezium/json/TestCompatibleDebeziumJsonSerializationSchema.java b/seatunnel-formats/seatunnel-format-compatible-debezium-json/src/test/java/org/apache/seatunnel/format/compatible/debezium/json/TestCompatibleDebeziumJsonSerializationSchema.java
new file mode 100644
index 00000000000..35117080f06
--- /dev/null
+++ b/seatunnel-formats/seatunnel-format-compatible-debezium-json/src/test/java/org/apache/seatunnel/format/compatible/debezium/json/TestCompatibleDebeziumJsonSerializationSchema.java
@@ -0,0 +1,39 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.seatunnel.format.compatible.debezium.json;
+
+import org.apache.seatunnel.api.table.type.SeaTunnelRow;
+import org.apache.seatunnel.api.table.type.SeaTunnelRowType;
+
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+public class TestCompatibleDebeziumJsonSerializationSchema {
+
+    @Test
+    public void testDebeziumSerializeKeyIsNull() {
+        SeaTunnelRowType rowType =
+                CompatibleDebeziumJsonDeserializationSchema.DEBEZIUM_DATA_ROW_TYPE;
+        SeaTunnelRow row = new SeaTunnelRow(new Object[] {"test_topic", null, "value"});
+
+        CompatibleDebeziumJsonSerializationSchema serializationSchema =
+                new CompatibleDebeziumJsonSerializationSchema(rowType, true);
+        Assertions.assertNull(serializationSchema.serialize(row));
+    }
+}