diff --git a/src/litdata/streaming/reader.py b/src/litdata/streaming/reader.py
index 078c9fa2..cfbe8d43 100644
--- a/src/litdata/streaming/reader.py
+++ b/src/litdata/streaming/reader.py
@@ -336,7 +336,7 @@ def __getstate__(self) -> Dict[str, Any]:
         return state
 
     def __del__(self) -> None:
-        if self._prepare_thread and not self._prepare_thread._has_exited:
+        if hasattr(self, "_prepare_thread") and self._prepare_thread and not self._prepare_thread._has_exited:
             self._prepare_thread.force_stop()
             self._prepare_thread = None