diff --git a/connectors/mongodb-connector/src/main/java/io/tapdata/mongodb/MongodbUtil.java b/connectors/mongodb-connector/src/main/java/io/tapdata/mongodb/MongodbUtil.java
index a25a25586..4f6389e8e 100644
--- a/connectors/mongodb-connector/src/main/java/io/tapdata/mongodb/MongodbUtil.java
+++ b/connectors/mongodb-connector/src/main/java/io/tapdata/mongodb/MongodbUtil.java
@@ -34,9 +34,9 @@
 import java.security.cert.CertificateException;
 import java.security.cert.X509Certificate;
 import java.util.*;
-import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicReference;
 import java.util.function.Consumer;
+import java.util.regex.Pattern;
 import java.util.stream.Collectors;
 import java.util.stream.IntStream;
 
@@ -286,6 +286,28 @@ public static String replicaSetUsedIn(String addresses) {
 		return addresses.substring(0, index);
 	}
 
+	private static final String[][] DEFAULT_HA_TIMEOUT_OPTIONS = {
+			{"serverSelectionTimeoutMS", "15000"},
+			{"socketTimeoutMS", "15000"},
+			{"maxIdleTimeMS", "30000"}
+	};
+
+	public static String appendDefaultHaTimeoutOptions(String mongodbUri) {
+		if (EmptyKit.isBlank(mongodbUri)) {
+			return mongodbUri;
+		}
+		StringBuilder result = new StringBuilder(mongodbUri);
+		for (String[] kv : DEFAULT_HA_TIMEOUT_OPTIONS) {
+			String key = kv[0];
+			String value = kv[1];
+			Pattern pattern = Pattern.compile("[?&]" + Pattern.quote(key) + "=", Pattern.CASE_INSENSITIVE);
+			if (!pattern.matcher(result).find()) {
+				result.append(result.indexOf("?") >= 0 ? '&' : '?').append(key).append('=').append(value);
+			}
+		}
+		return result.toString();
+	}
+
 	public static String getMongoDBURIOptions(String databaseUri) {
 		String options = null;
 		try {
@@ -479,6 +501,7 @@ public static MongoClient createMongoClient(MongodbConfig mongodbConfig) {
 	}
 
 	public static MongoClientSettings.Builder getMongoClientSettingsBuilder(String mongodbUri, MongodbConfig mongodbConfig) {
+		mongodbUri = appendDefaultHaTimeoutOptions(mongodbUri);
 		CodecRegistry defaultCodecRegistry = MongoClientSettings.getDefaultCodecRegistry();
 		CodecRegistry codecRegistry = CodecRegistries.fromRegistries(CodecRegistries.fromCodecs(
 				new TapdataBigDecimalCodec(),
diff --git a/connectors/mongodb-connector/src/main/java/io/tapdata/mongodb/reader/v3/MongodbV3StreamReader.java b/connectors/mongodb-connector/src/main/java/io/tapdata/mongodb/reader/v3/MongodbV3StreamReader.java
index 500240fa6..af0a455de 100644
--- a/connectors/mongodb-connector/src/main/java/io/tapdata/mongodb/reader/v3/MongodbV3StreamReader.java
+++ b/connectors/mongodb-connector/src/main/java/io/tapdata/mongodb/reader/v3/MongodbV3StreamReader.java
@@ -222,7 +222,7 @@ private void readFromOplog(TapConnectorContext connectorContext, String replicaS
 
 		final Bson fromMigrateFilter = Filters.exists("fromMigrate", false);
 
-		try (MongoClient mongoclient = MongoClients.create(mongodbURI)) {
+		try (MongoClient mongoclient = MongoClients.create(MongodbUtil.appendDefaultHaTimeoutOptions(mongodbURI))) {
 			final MongoCollection<Document> oplogCollection = mongoclient.getDatabase(LOCAL_DATABASE).getCollection(OPLOG_COLLECTION);
 			try (final MongoCursor<Document> mongoCursor = oplogCollection.find(fromMigrateFilter).sort(new Document("$natural", 1)).limit(1).cursorType(CursorType.TailableAwait)
 				.noCursorTimeout(true).iterator()) {
diff --git a/connectors/mongodb-connector/src/test/java/io/tapdata/mongodb/MongodbUtilTest.java b/connectors/mongodb-connector/src/test/java/io/tapdata/mongodb/MongodbUtilTest.java
index 2314b5f83..961132463 100644
--- a/connectors/mongodb-connector/src/test/java/io/tapdata/mongodb/MongodbUtilTest.java
+++ b/connectors/mongodb-connector/src/test/java/io/tapdata/mongodb/MongodbUtilTest.java
@@ -72,4 +72,56 @@ void test_load_oplog(){
             verify(callback,times(1)).accept(any());
         }
     }
+
+    @Nested
+    class appendDefaultHaTimeoutOptionsTest {
+        @Test
+        void noQueryString_appendsAllThree() {
+            String uri = "mongodb://host:27017/db";
+            String result = MongodbUtil.appendDefaultHaTimeoutOptions(uri);
+            Assertions.assertEquals(
+                    "mongodb://host:27017/db?serverSelectionTimeoutMS=15000&socketTimeoutMS=15000&maxIdleTimeMS=30000",
+                    result);
+        }
+
+        @Test
+        void existingAuthSource_appendsWithAmpersand() {
+            String uri = "mongodb://u:p@host/db?authSource=admin";
+            String result = MongodbUtil.appendDefaultHaTimeoutOptions(uri);
+            Assertions.assertEquals(
+                    "mongodb://u:p@host/db?authSource=admin&serverSelectionTimeoutMS=15000&socketTimeoutMS=15000&maxIdleTimeMS=30000",
+                    result);
+        }
+
+        @Test
+        void userSocketTimeoutPreserved_otherTwoAdded() {
+            String uri = "mongodb://host/db?socketTimeoutMS=5000";
+            String result = MongodbUtil.appendDefaultHaTimeoutOptions(uri);
+            Assertions.assertTrue(result.contains("socketTimeoutMS=5000"));
+            Assertions.assertFalse(result.contains("socketTimeoutMS=15000"));
+            Assertions.assertTrue(result.contains("serverSelectionTimeoutMS=15000"));
+            Assertions.assertTrue(result.contains("maxIdleTimeMS=30000"));
+        }
+
+        @Test
+        void allThreeAlreadySet_returnsUnchanged() {
+            String uri = "mongodb://host/db?serverSelectionTimeoutMS=20000&socketTimeoutMS=10000&maxIdleTimeMS=45000";
+            String result = MongodbUtil.appendDefaultHaTimeoutOptions(uri);
+            Assertions.assertEquals(uri, result);
+        }
+
+        @Test
+        void caseInsensitiveKey_notDuplicated() {
+            String uri = "mongodb://host/db?SocketTimeoutMS=5000";
+            String result = MongodbUtil.appendDefaultHaTimeoutOptions(uri);
+            Assertions.assertTrue(result.contains("SocketTimeoutMS=5000"));
+            Assertions.assertFalse(result.contains("socketTimeoutMS=15000"));
+        }
+
+        @Test
+        void blankUri_returnedAsIs() {
+            Assertions.assertNull(MongodbUtil.appendDefaultHaTimeoutOptions(null));
+            Assertions.assertEquals("", MongodbUtil.appendDefaultHaTimeoutOptions(""));
+        }
+    }
 }