diff --git a/google-cloud-pubsub/src/main/java/com/google/cloud/pubsub/v1/StatusUtil.java b/google-cloud-pubsub/src/main/java/com/google/cloud/pubsub/v1/StatusUtil.java
index ab31f0320..a7b8e1faa 100644
--- a/google-cloud-pubsub/src/main/java/com/google/cloud/pubsub/v1/StatusUtil.java
+++ b/google-cloud-pubsub/src/main/java/com/google/cloud/pubsub/v1/StatusUtil.java
@@ -36,6 +36,7 @@ static boolean isRetryable(Throwable error) {
       case CANCELLED:
       case RESOURCE_EXHAUSTED:
       case ABORTED:
+      case UNKNOWN:
         return true;
       case UNAVAILABLE:
         // TODO(pongad): check that ApiException propagate message properly.