diff --git a/src/sql/engine/px/ob_px_task_process.cpp b/src/sql/engine/px/ob_px_task_process.cpp
index b6333a0424aac4e2b985a6fe3b41375d9380c1fb..c3532e7d37936610d93a5df74671c198bd67eb90 100644
--- a/src/sql/engine/px/ob_px_task_process.cpp
+++ b/src/sql/engine/px/ob_px_task_process.cpp
@@ -225,6 +225,7 @@ int ObPxTaskProcess::process()
       }
     }
   }
+  release();
   ObActiveSessionGuard::get_stat().in_px_execution_ = false;
   return ret;
 }