diff --git a/qlib/utils/paral.py b/qlib/utils/paral.py
index a617783341..77ededb857 100644
--- a/qlib/utils/paral.py
+++ b/qlib/utils/paral.py
@@ -21,13 +21,14 @@ class ParallelExt(Parallel):
     def __init__(self, *args, **kwargs):
         maxtasksperchild = kwargs.pop("maxtasksperchild", None)
         super(ParallelExt, self).__init__(*args, **kwargs)
-        if isinstance(self._backend, MultiprocessingBackend):
+        if isinstance(self._backend, MultiprocessingBackend) and maxtasksperchild is not None:
             # 2025-05-04 joblib released version 1.5.0, in which _backend_args was removed and replaced by _backend_kwargs.
             # Ref: https://github.com/joblib/joblib/pull/1525/files#diff-e4dff8042ce45b443faf49605b75a58df35b8c195978d4a57f4afa695b406bdc
-            if joblib.__version__ < "1.5.0":
-                self._backend_args["maxtasksperchild"] = maxtasksperchild  # pylint: disable=E1101
-            else:
+            # Check for attribute existence instead of version comparison to be more robust
+            if hasattr(self, '_backend_kwargs'):
                 self._backend_kwargs["maxtasksperchild"] = maxtasksperchild  # pylint: disable=E1101
+            elif hasattr(self, '_backend_args'):
+                self._backend_args["maxtasksperchild"] = maxtasksperchild  # pylint: disable=E1101
 
 
 def datetime_groupby_apply(