diff --git a/pulsar-client/src/main/java/org/apache/pulsar/client/impl/ConsumerImpl.java b/pulsar-client/src/main/java/org/apache/pulsar/client/impl/ConsumerImpl.java
index 199e8a9ae71b4..1438f65ec5ce5 100644
--- a/pulsar-client/src/main/java/org/apache/pulsar/client/impl/ConsumerImpl.java
+++ b/pulsar-client/src/main/java/org/apache/pulsar/client/impl/ConsumerImpl.java
@@ -346,17 +346,17 @@ protected ConsumerImpl(PulsarClientImpl client, String topic, ConsumerConfigurat
             } else {
                 this.deadLetterPolicy = DeadLetterPolicy.builder()
                         .maxRedeliverCount(conf.getDeadLetterPolicy().getMaxRedeliverCount())
-                        .deadLetterTopic(String.format("%s-%s" + RetryMessageUtil.DLQ_GROUP_TOPIC_SUFFIX,
-                                topic, subscription))
+                        .deadLetterTopic(StringUtils.appendIfMissing(String.format("%s-%s",
+                                topic, subscription), RetryMessageUtil.DLQ_GROUP_TOPIC_SUFFIX))
                         .build();
             }
 
             if (StringUtils.isNotBlank(conf.getDeadLetterPolicy().getRetryLetterTopic())) {
                 this.deadLetterPolicy.setRetryLetterTopic(conf.getDeadLetterPolicy().getRetryLetterTopic());
             } else {
-                this.deadLetterPolicy.setRetryLetterTopic(String.format(
-                        "%s-%s" + RetryMessageUtil.RETRY_GROUP_TOPIC_SUFFIX,
-                        topic, subscription));
+                this.deadLetterPolicy.setRetryLetterTopic(StringUtils.appendIfMissing(
+                    String.format("%s-%s", topic, subscription),
+                    RetryMessageUtil.RETRY_GROUP_TOPIC_SUFFIX));
             }
 
             if (StringUtils.isNotBlank(conf.getDeadLetterPolicy().getInitialSubscriptionName())) {