diff --git a/dios/dios.py b/dios/dios.py
index 7af955c1ecf59217ce5997bb6740b5e513f65704..497135eafa12bd522ca25d00d8e319a063294c59 100644
--- a/dios/dios.py
+++ b/dios/dios.py
@@ -895,6 +895,8 @@ def _is_bool_dios_like(obj) -> bool:
 
 
 def to_dios(obj) -> DictOfSeries:
+    if isinstance(obj, DictOfSeries):
+        return obj
     return DictOfSeries(data=obj)