diff --git a/src/operator/tensor/matrix_op-inl.h b/src/operator/tensor/matrix_op-inl.h
index 217bf10398ad..46bb20a880cb 100644
--- a/src/operator/tensor/matrix_op-inl.h
+++ b/src/operator/tensor/matrix_op-inl.h
@@ -1094,7 +1094,7 @@ inline bool SliceAssignOpShape(const nnvm::NodeAttrs& attrs,
     common::StaticArray<index_t, ndim> begin, end, step;
     GetIndexRange(dshape, param.begin, param.end, param.step, &begin, &end, &step);
     for (int i = 0; i < param.begin.ndim(); ++i) {
-      const int b = begin[i], e = end[i], s = step[i];
+      const index_t b = begin[i], e = end[i], s = step[i];
       SetSliceOpOutputDimSize(dshape, i, b, e, s, &vshape);
     }
   })
@@ -1137,7 +1137,7 @@ void SliceAssignOpForward(const nnvm::NodeAttrs& attrs,
     }
     MSHADOW_TYPE_SWITCH(out.type_flag_, DType, {
       MXNET_ASSIGN_REQ_SWITCH(req[0], Req, {
-        int num_threads = val.shape_.FlatTo2D()[0];
+        index_t num_threads = val.shape_.FlatTo2D()[0];
         if (std::is_same<xpu, gpu>::value) {
           num_threads *= val.shape_.get<ndim>()[ndim - 1];
         }
@@ -1241,7 +1241,7 @@ void SliceAssignScalarOpForward(const nnvm::NodeAttrs& attrs,
       return;  // slice_assign of zero-sized subspaced needs no operation.
     }
     for (index_t i = 0; i < param.begin.ndim(); ++i) {
-      const int b = begin[i], e = end[i], s = step[i];
+      const index_t b = begin[i], e = end[i], s = step[i];
       SetSliceOpOutputDimSize(data.shape_, i, b, e, s, &vshape);
     }
     MSHADOW_TYPE_SWITCH_WITH_BOOL(out.type_flag_, DType, {
diff --git a/tests/nightly/test_large_array.py b/tests/nightly/test_large_array.py
index d93d1835a1ec..b7a27c3f4302 100644
--- a/tests/nightly/test_large_array.py
+++ b/tests/nightly/test_large_array.py
@@ -2020,6 +2020,17 @@ def test_sparse_dot():
     assert out.shape == (2, 2)
 
 
+def test_slice_assign():
+    # test _slice_assign
+    A = np.zeros((2**31, 2))
+    A[-1] = np.ones((1))
+    assert A[-1, 0] == 1 and A[-1, 1] == 1
+    # test _slice_assign_scalar
+    B = np.zeros((2**31, 2))
+    B[-1] = 2
+    assert B[-1, 0] == 2 and B[-1, 1] == 2
+
+
 if __name__ == '__main__':
     import nose
     nose.runmodule()