diff --git a/pandas/tests/frame/methods/test_fillna.py b/pandas/tests/frame/methods/test_fillna.py
index 8915d6f205d65..0868fcf573918 100644
--- a/pandas/tests/frame/methods/test_fillna.py
+++ b/pandas/tests/frame/methods/test_fillna.py
@@ -257,6 +257,19 @@ def test_fillna_categorical_nan(self):
         df = DataFrame({"a": Categorical(idx)})
         tm.assert_frame_equal(df.fillna(value=NaT), df)
 
+    def test_fillna_with_categorical_series(self):
+        df = DataFrame(
+            {"cats": Categorical(["A", "B", "C"]), "ints": [1.0, 2.0, np.nan]}
+        )
+
+        filler = Series(Categorical([10.0, 20.0, 30.0]))
+        df.fillna({"ints": filler}, inplace=True)
+
+        expected = DataFrame(
+            {"cats": Categorical(["A", "B", "C"]), "ints": [1.0, 2.0, 30.0]}
+        )
+        tm.assert_frame_equal(df, expected)
+
     def test_fillna_no_downcast(self, frame_or_series):
         # GH#45603 preserve object dtype
         obj = frame_or_series([1, 2, 3], dtype="object")