diff --git a/modules/python/src2/cv2_util.cpp b/modules/python/src2/cv2_util.cpp
index e5751045df..5858c6372b 100644
--- a/modules/python/src2/cv2_util.cpp
+++ b/modules/python/src2/cv2_util.cpp
@@ -47,6 +47,8 @@ int numpyTypeToCvDepth(int typenum)
     // 'long' is 64-bit on LP64 but 32-bit on LLP64, so decide by size, not by name.
     case NPY_LONG:      return NPY_SIZEOF_LONG == 8 ? CV_64S : CV_32S;
     case NPY_ULONG:     return NPY_SIZEOF_LONG == 8 ? CV_64U : CV_32U;
+    // Map the 32-bit case: it is numpy's int32 on LLP64, and output arrays cannot be cast.
+    case NPY_LONG:      return NPY_SIZEOF_LONG == 4 ? CV_32S : -1;
     case NPY_HALF:      return CV_16F;
     case NPY_FLOAT:     return CV_32F;
     case NPY_DOUBLE:    return CV_64F;
diff --git a/modules/python/test/test_misc.py b/modules/python/test/test_misc.py
index c6469f7226..73cb6039ab 100644
--- a/modules/python/test/test_misc.py
+++ b/modules/python/test/test_misc.py
@@ -318,6 +318,11 @@ class Arguments(NewOpenCVTests):
         #res6 = cv.utils.dumpInputArray([a, b])
         #self.assertEqual(res6, "InputArrayOfArrays: empty()=false kind=0x00050000 flags=0x01050000 total(-1)=2 dims(-1)=1 size(-1)=2x1 type(0)=CV_32FC1 dims(0)=4 size(0)=[2 3 4 5]")
 
+    def test_InputOutputArray(self):
+        a = np.zeros((2, 3), dtype=np.int32)
+        res, _ = cv.utils.dumpInputOutputArray(a)
+        self.assertIn('type(-1)=CV_32SC1', res)
+
     def test_unsupported_numpy_data_types_string_description(self):
         for dtype in (object, str, np.complex128):
             test_array = np.zeros((4, 4, 3), dtype=dtype)