diff --git a/ptodsl/ptodsl/_ops.py b/ptodsl/ptodsl/_ops.py
index 365ec64b04..cfe46b4f13 100644
--- a/ptodsl/ptodsl/_ops.py
+++ b/ptodsl/ptodsl/_ops.py
@@ -63,7 +63,6 @@
     _materialize_integer_literal,
     _normalize_address_space,
     _resolve,
-    _strip_integer_signedness,
     mask_type,
     part_tensor_view_type,
     part_tensor_view_type_from_dims,
@@ -2032,13 +2031,12 @@ def _infer_vdup_scalar_result_type(input_value, mask_value, *, context: str):
     scalar_type = scalar_raw.type
     mask_bits = _mask_granularity_bits(mask_value, context=context)
     if IntegerType.isinstance(scalar_type):
-        scalar_type = _strip_integer_signedness(scalar_raw)
-        scalar_width = IntegerType(scalar_type.type).width
+        scalar_width = IntegerType(scalar_type).width
         if scalar_width != mask_bits:
             raise TypeError(
                 f"{context} expects scalar input width {scalar_width} to match mask granularity b{mask_bits}"
             )
-        element_type = scalar_type.type
+        element_type = scalar_type
     elif F16Type.isinstance(scalar_type) or BF16Type.isinstance(scalar_type):
         if mask_bits != 16:
             raise TypeError(f"{context} expects f16/bf16 scalar input to pair with mask_b16, got mask_b{mask_bits}")
@@ -2090,6 +2088,12 @@ def vdup(input_value, mask, position=None):
             raise TypeError("vdup(scalar, mask, position=...) does not support position; position is only valid for vector input")
         raw_input = _coerce_vdup_scalar_input(input_value, mask, context="vdup(scalar, mask)")
         result_type = _infer_vdup_scalar_result_type(raw_input, mask, context="vdup(scalar, mask)")
+        result_element_type = _pto.VRegType(result_type).element_type
+        raw_input = coerce_scalar_to_type(
+            raw_input,
+            result_element_type,
+            context="vdup(scalar, mask)",
+        )
         normalized_position = None
     return wrap_surface_value(
         _pto.VdupOp(
diff --git a/ptodsl/tests/test_issue_1102_vdup.py b/ptodsl/tests/test_issue_1102_vdup.py
new file mode 100644
index 0000000000..83d8b749e8
--- /dev/null
+++ b/ptodsl/tests/test_issue_1102_vdup.py
@@ -0,0 +1,59 @@
+#!/usr/bin/env python3
+# Copyright (c) 2026 Huawei Technologies Co., Ltd.
+# This program is free software, you can redistribute it and/or modify it under the terms and conditions of
+# CANN Open Software License Agreement Version 2.0 (the "License").
+# Please refer to the License for details. You may not use this file except in compliance with the License.
+# THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND, EITHER EXPRESS OR IMPLIED,
+# INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT, MERCHANTABILITY, OR FITNESS FOR A PARTICULAR PURPOSE.
+# See LICENSE in the root of the software repository for the full text of the License.
+
+from ptodsl import pto
+
+
+def _compile_vdup(name, dtype, mask_bits, value):
+    @pto.jit(name=name, kernel_kind="vector", target="a5", mode="explicit")
+    def kernel():
+        mask = getattr(pto, f"pset_b{mask_bits}")(pto.MaskPattern.ALL)
+        pto.vdup(pto.const(value, dtype=dtype), mask)
+
+    return kernel.compile().mlir_text()
+
+
+def _compile_vdup_consumer():
+    @pto.jit(name="issue_1102_vdup_vor", kernel_kind="vector", target="a5", mode="explicit")
+    def kernel():
+        base = pto.const(0, dtype=pto.ui64)
+        source = pto.castptr(base, pto.ptr(pto.ui16, "ub"))
+        mask = pto.pset_b16(pto.MaskPattern.ALL)
+        loaded = pto.vlds(source, pto.const(0))
+        duplicated = pto.vdup(pto.ui16(1), mask)
+        pto.vor(loaded, duplicated, mask)
+
+    return kernel.compile().mlir_text()
+
+
+def main():
+    cases = (
+        ("i8", pto.i8, 8, 1, "i8, !pto.mask<b8> -> !pto.vreg<256xi8>"),
+        ("si8", pto.si8, 8, 1, "si8, !pto.mask<b8> -> !pto.vreg<256xsi8>"),
+        ("ui8", pto.ui8, 8, 1, "ui8, !pto.mask<b8> -> !pto.vreg<256xui8>"),
+        ("i16", pto.i16, 16, 1, "i16, !pto.mask<b16> -> !pto.vreg<128xi16>"),
+        ("si16", pto.si16, 16, 1, "si16, !pto.mask<b16> -> !pto.vreg<128xsi16>"),
+        ("ui16", pto.ui16, 16, 1, "ui16, !pto.mask<b16> -> !pto.vreg<128xui16>"),
+        ("i32", pto.i32, 32, 1, "i32, !pto.mask<b32> -> !pto.vreg<64xi32>"),
+        ("si32", pto.si32, 32, 1, "si32, !pto.mask<b32> -> !pto.vreg<64xsi32>"),
+        ("ui32", pto.ui32, 32, 1, "ui32, !pto.mask<b32> -> !pto.vreg<64xui32>"),
+    )
+    for name, dtype, mask_bits, value, expected_type in cases:
+        text = _compile_vdup(f"issue_1102_vdup_{name}", dtype, mask_bits, value)
+        if expected_type not in text:
+            raise AssertionError(
+                f"{name} vdup should preserve the scalar integer signedness in its result vector; "
+                f"expected {expected_type!r} in:\n{text}"
+            )
+    _compile_vdup_consumer()
+    print("issue_1102_vdup: PASS")
+
+
+if __name__ == "__main__":
+    main()