diff --git a/rest_api/config.py b/rest_api/config.py
index b974fa88f..4317036b7 100644
--- a/rest_api/config.py
+++ b/rest_api/config.py
@@ -9,4 +9,4 @@ FILE_UPLOAD_PATH = os.getenv("FILE_UPLOAD_PATH", "./file-upload")
 LOG_LEVEL = os.getenv("LOG_LEVEL", "INFO")
 ROOT_PATH = os.getenv("ROOT_PATH", "/")
 
-CONCURRENT_REQUEST_PER_WORKER = os.getenv("CONCURRENT_REQUEST_PER_WORKER", 4)
+CONCURRENT_REQUEST_PER_WORKER = int(os.getenv("CONCURRENT_REQUEST_PER_WORKER", 4))