diff --git a/pandas/core/arrays/datetimelike.py b/pandas/core/arrays/datetimelike.py
index 8928c72de750c..91dd40c2deced 100644
--- a/pandas/core/arrays/datetimelike.py
+++ b/pandas/core/arrays/datetimelike.py
@@ -770,7 +770,7 @@ def isin(self, values: ArrayLike) -> npt.NDArray[np.bool_]:
             ]
             if values.dtype == object:
                 values = lib.maybe_convert_objects(
-                    values,
+                    values,  # type: ignore[arg-type]
                     convert_non_numeric=True,
                     dtype_if_all_nat=self.dtype,
                 )