diff --git a/pandas/core/arrays/string_arrow.py b/pandas/core/arrays/string_arrow.py
index 8f93025b57d20..9a287c9ea1ea7 100644
--- a/pandas/core/arrays/string_arrow.py
+++ b/pandas/core/arrays/string_arrow.py
@@ -555,7 +555,7 @@ def _str_map(
     def _convert_int_dtype(self, result):
         if isinstance(result, pa.Array):
             result = result.to_numpy(zero_copy_only=False)
-        else:
+        elif not isinstance(result, np,ndarray):
             result = result.to_numpy()
         if result.dtype == np.int32:
             result = result.astype(np.int64)