diff --git a/pulsar-io/debezium/core/src/main/java/org/apache/pulsar/io/debezium/DebeziumSource.java b/pulsar-io/debezium/core/src/main/java/org/apache/pulsar/io/debezium/DebeziumSource.java
index 497e718d..62c3984 100644
--- a/pulsar-io/debezium/core/src/main/java/org/apache/pulsar/io/debezium/DebeziumSource.java
+++ b/pulsar-io/debezium/core/src/main/java/org/apache/pulsar/io/debezium/DebeziumSource.java
@@ -19,7 +19,6 @@
 package org.apache.pulsar.io.debezium;
 
 import io.debezium.relational.HistorizedRelationalDatabaseConnectorConfig;
-import io.debezium.relational.history.DatabaseHistory;
 import java.util.Map;
 import org.apache.commons.lang3.StringUtils;
 import org.apache.pulsar.common.naming.TopicName;
@@ -49,10 +48,7 @@
     }
 
     public static void setConfigIfNull(Map<String, Object> config, String key, String value) {
-        Object orig = config.get(key);
-        if (orig == null) {
-            config.put(key, value);
-        }
+        config.putIfAbsent(key, value);
     }
 
     // namespace for output topics, default value is "tenant/namespace"
@@ -80,9 +76,6 @@
 
         // database.history.pulsar.service.url
         String pulsarUrl = (String) config.get(PulsarDatabaseHistory.SERVICE_URL.name());
-        if (StringUtils.isEmpty(pulsarUrl)) {
-            throw new IllegalArgumentException("Pulsar service URL for History Database not provided.");
-        }
 
         String topicNamespace = topicNamespace(sourceContext);
         // topic.namespace
@@ -96,8 +89,11 @@
         setConfigIfNull(config, PulsarKafkaWorkerConfig.OFFSET_STORAGE_TOPIC_CONFIG,
             topicNamespace + "/" + sourceName + "-" + DEFAULT_OFFSET_TOPIC);
 
-        config.put(DatabaseHistory.CONFIGURATION_FIELD_PREFIX_STRING + "pulsar.client.builder",
-                SerDeUtils.serialize(sourceContext.getPulsarClientBuilder()));
+        // pass pulsar.client.builder if database.history.pulsar.service.url is not provided
+        if (StringUtils.isEmpty(pulsarUrl)) {
+            String pulsarClientBuilder = SerDeUtils.serialize(sourceContext.getPulsarClientBuilder());
+            config.put(PulsarDatabaseHistory.CLIENT_BUILDER.name(), pulsarClientBuilder);
+        }
 
         super.open(config, sourceContext);
     }
diff --git a/pulsar-io/debezium/core/src/main/java/org/apache/pulsar/io/debezium/PulsarDatabaseHistory.java b/pulsar-io/debezium/core/src/main/java/org/apache/pulsar/io/debezium/PulsarDatabaseHistory.java
index 36fb73a..f004d24 100644
--- a/pulsar-io/debezium/core/src/main/java/org/apache/pulsar/io/debezium/PulsarDatabaseHistory.java
+++ b/pulsar-io/debezium/core/src/main/java/org/apache/pulsar/io/debezium/PulsarDatabaseHistory.java
@@ -103,12 +103,12 @@
         }
         this.topicName = config.getString(TOPIC);
 
-        if (config.getString(CLIENT_BUILDER) == null && config.getString(SERVICE_URL) == null) {
+        String clientBuilderBase64Encoded = config.getString(CLIENT_BUILDER);
+        if (isBlank(clientBuilderBase64Encoded) && isBlank(config.getString(SERVICE_URL))) {
             throw new IllegalArgumentException("Neither Pulsar Service URL nor ClientBuilder provided.");
         }
-        String clientBuilderBase64Encoded = config.getString(CLIENT_BUILDER);
         this.clientBuilder = PulsarClient.builder();
-        if (null != clientBuilderBase64Encoded) {
+        if (!isBlank(clientBuilderBase64Encoded)) {
             // deserialize the client builder to the same classloader
             this.clientBuilder = (ClientBuilder) SerDeUtils.deserialize(clientBuilderBase64Encoded,
                     this.clientBuilder.getClass().getClassLoader());
diff --git a/tests/integration/src/test/java/org/apache/pulsar/tests/integration/io/sources/debezium/DebeziumMySqlSourceTester.java b/tests/integration/src/test/java/org/apache/pulsar/tests/integration/io/sources/debezium/DebeziumMySqlSourceTester.java
index 3cb64db..7958fa0 100644
--- a/tests/integration/src/test/java/org/apache/pulsar/tests/integration/io/sources/debezium/DebeziumMySqlSourceTester.java
+++ b/tests/integration/src/test/java/org/apache/pulsar/tests/integration/io/sources/debezium/DebeziumMySqlSourceTester.java
@@ -49,7 +49,8 @@
 
     private final PulsarCluster pulsarCluster;
 
-    public DebeziumMySqlSourceTester(PulsarCluster cluster, String converterClassName) {
+    public DebeziumMySqlSourceTester(PulsarCluster cluster, String converterClassName,
+                                     boolean testWithClientBuilder) {
         super(NAME);
         this.pulsarCluster = cluster;
         pulsarServiceUrl = "pulsar://pulsar-proxy:" + PulsarContainer.BROKER_PORT;
@@ -61,7 +62,9 @@
         sourceConfig.put("database.server.id", "184054");
         sourceConfig.put("database.server.name", "dbserver1");
         sourceConfig.put("database.whitelist", "inventory");
-        sourceConfig.put("database.history.pulsar.service.url", pulsarServiceUrl);
+        if (!testWithClientBuilder) {
+            sourceConfig.put("database.history.pulsar.service.url", pulsarServiceUrl);
+        }
         sourceConfig.put("key.converter", converterClassName);
         sourceConfig.put("value.converter", converterClassName);
         sourceConfig.put("topic.namespace", "debezium/mysql-" +
diff --git a/tests/integration/src/test/java/org/apache/pulsar/tests/integration/io/sources/debezium/PulsarDebeziumSourcesTest.java b/tests/integration/src/test/java/org/apache/pulsar/tests/integration/io/sources/debezium/PulsarDebeziumSourcesTest.java
index 9836319..246b52b 100644
--- a/tests/integration/src/test/java/org/apache/pulsar/tests/integration/io/sources/debezium/PulsarDebeziumSourcesTest.java
+++ b/tests/integration/src/test/java/org/apache/pulsar/tests/integration/io/sources/debezium/PulsarDebeziumSourcesTest.java
@@ -45,13 +45,18 @@
 
     @Test(groups = "source")
     public void testDebeziumMySqlSourceJson() throws Exception {
-        testDebeziumMySqlConnect("org.apache.kafka.connect.json.JsonConverter", true);
+        testDebeziumMySqlConnect("org.apache.kafka.connect.json.JsonConverter", true, false);
+    }
+
+    @Test(groups = "source")
+    public void testDebeziumMySqlSourceJsonWithClientBuilder() throws Exception {
+        testDebeziumMySqlConnect("org.apache.kafka.connect.json.JsonConverter", true, true);
     }
 
     @Test(groups = "source")
     public void testDebeziumMySqlSourceAvro() throws Exception {
         testDebeziumMySqlConnect(
-                "org.apache.pulsar.kafka.shade.io.confluent.connect.avro.AvroConverter", false);
+                "org.apache.pulsar.kafka.shade.io.confluent.connect.avro.AvroConverter", false, false);
     }
 
     @Test(groups = "source")
@@ -59,6 +64,7 @@
         testDebeziumPostgreSqlConnect("org.apache.kafka.connect.json.JsonConverter", true);
     }
 
+
     @Test(groups = "source")
     public void testDebeziumMongoDbSource() throws Exception{
         testDebeziumMongoDbConnect("org.apache.kafka.connect.json.JsonConverter", true);
@@ -69,7 +75,8 @@
         testDebeziumMsSqlConnect("org.apache.kafka.connect.json.JsonConverter", true);
     }
 
-    private void testDebeziumMySqlConnect(String converterClassName, boolean jsonWithEnvelope) throws Exception {
+    private void testDebeziumMySqlConnect(String converterClassName, boolean jsonWithEnvelope,
+                                          boolean testWithClientBuilder) throws Exception {
 
         final String tenant = TopicName.PUBLIC_TENANT;
         final String namespace = TopicName.DEFAULT_NAMESPACE;
@@ -104,7 +111,7 @@
         admin.topics().createNonPartitionedTopic(outputTopicName);
 
         @Cleanup
-        DebeziumMySqlSourceTester sourceTester = new DebeziumMySqlSourceTester(pulsarCluster, converterClassName);
+        DebeziumMySqlSourceTester sourceTester = new DebeziumMySqlSourceTester(pulsarCluster, converterClassName, testWithClientBuilder);
         sourceTester.getSourceConfig().put("json-with-envelope", jsonWithEnvelope);
 
         // setup debezium mysql server