diff --git a/Tools/ModelTranslator/model_decimate.py b/Tools/ModelTranslator/model_decimate.py
index 4b5109b8..80b91d7b 100644
--- a/Tools/ModelTranslator/model_decimate.py
+++ b/Tools/ModelTranslator/model_decimate.py
@@ -5,6 +5,7 @@ import argparse
 import os
 
 from mt_run import find_blender, run_blender_script
+from qr_bridge import QR_INPUT_CAP
 
 
 def main():
@@ -16,6 +17,8 @@ def main():
                     help="UV 展开：seam=锐边接缝整岛展开（默认），smart=Smart UV Project")
     ap.add_argument("--reducer", choices=("collapse", "quad"), default="quad",
                     help="减面后端：quad=Quad Remesher 四边重拓扑（默认，失败自动回退 collapse），collapse=Decimate 塌陷")
+    ap.add_argument("--qr-input-cap", type=int, default=QR_INPUT_CAP,
+                    help="quad 后端 QR 前预 collapse 的中等密度目标面数（默认 50000）；高密度模型直接 QR 会破洞")
     ap.add_argument("--max-overlap", type=float, default=None,
                     help="UV 重叠容忍上限（0-1，默认内置 0.08）；调高可让更高 seam 角度过门、减少碎岛")
     ap.add_argument("--blender", default=None)
@@ -24,6 +27,8 @@ def main():
         ap.error("--tris 必须为正整数")
     if args.max_overlap is not None and not (0.0 < args.max_overlap <= 1.0):
         ap.error("--max-overlap 必须在 (0, 1] 内")
+    if args.qr_input_cap <= 0:
+        ap.error("--qr-input-cap 必须为正整数")
 
     blender = find_blender(args.blender)
     name = os.path.splitext(os.path.basename(args.input))[0]
@@ -33,7 +38,7 @@ def main():
     s = run_blender_script(blender, "bl_decimate.py",
                            [args.input, out_fbx, str(args.tris), args.unwrap,
                             "" if args.max_overlap is None else str(args.max_overlap),
-                            args.reducer])
+                            args.reducer, str(args.qr_input_cap)])
 
     print("== %s: %d -> %d 面（目标 %d）-> %s" %
           (s["src"], s["tris_before"], s["tris_after"], s["target"], out_fbx))
diff --git a/Tools/ModelTranslator/tests/test_model_decimate_cli.py b/Tools/ModelTranslator/tests/test_model_decimate_cli.py
index def9fb48..17d8d653 100644
--- a/Tools/ModelTranslator/tests/test_model_decimate_cli.py
+++ b/Tools/ModelTranslator/tests/test_model_decimate_cli.py
@@ -32,7 +32,9 @@ class TestModelDecimateCli(unittest.TestCase):
             model_decimate.main()
 
         args = run.call_args.args[2]
-        self.assertEqual(args[-1], "quad")
+        # argv 顺序：input, out, tris, unwrap, overlap, reducer, qr_input_cap
+        self.assertEqual(args[5], "quad")           # reducer 默认 quad
+        self.assertEqual(args[6], "50000")          # qr_input_cap 默认 50000
 
 
 if __name__ == "__main__":