diff --git a/superset/utils/core.py b/superset/utils/core.py
index aa3a10a7b9ffd..5ccb74aa99fa1 100644
--- a/superset/utils/core.py
+++ b/superset/utils/core.py
@@ -26,6 +26,7 @@
 import signal
 import smtplib
 import tempfile
+import threading
 import traceback
 import uuid
 import zlib
@@ -631,8 +632,9 @@ def handle_timeout(  # pylint: disable=unused-argument
 
     def __enter__(self) -> None:
         try:
-            signal.signal(signal.SIGALRM, self.handle_timeout)
-            signal.alarm(self.seconds)
+            if threading.current_thread() == threading.main_thread():
+                signal.signal(signal.SIGALRM, self.handle_timeout)
+                signal.alarm(self.seconds)
         except ValueError as ex:
             logger.warning("timeout can't be used in the current context")
             logger.exception(ex)