diff --git a/projects/PTv3/README.md b/projects/PTv3/README.md
index 06ed1c204..3ebe061c2 100644
--- a/projects/PTv3/README.md
+++ b/projects/PTv3/README.md
@@ -58,11 +58,16 @@ Export the model:
 python projects/PTv3/tools/export.py --config-file projects/PTv3/configs/semseg-pt-v3m1-0-t4dataset.py --num-gpus 1 \
   --options \
   save_path=work_dirs/experiment \
-  weight=work_dirs/ptv3/model/model_best.pth
+  weight=work_dirs/ptv3/model/model_best.pth \
+  spconv_do_sort=False
 ```
 
 which will generate a file called `ptv3.onnx`
 
+- `spconv_do_sort` controls the ONNX attribute on `GetIndicePairsImplicitGemm`:
+  - `True` (default): export with sorting enabled (`do_sort=1`)
+  - `False`: export with sorting disabled (`do_sort=0`)
+
 ## Reference
 
 - [Pointcept's PTv3](https://github.com/Pointcept/Pointcept)
diff --git a/projects/PTv3/configs/_base_/default_runtime.py b/projects/PTv3/configs/_base_/default_runtime.py
index cca5bd789..21048be37 100644
--- a/projects/PTv3/configs/_base_/default_runtime.py
+++ b/projects/PTv3/configs/_base_/default_runtime.py
@@ -23,6 +23,10 @@
 
 mix_prob = 0
 param_dicts = None  # example: param_dicts = [dict(keyword="block", lr_scale=0.1)]
+# Sparse pair-gen sort for ONNX export:
+# - True  (default): keep pair-mask argsort.
+# - False          : export GetIndicePairsImplicitGemm with do_sort=0.
+spconv_do_sort = True
 
 # hook
 hooks = [
diff --git a/projects/PTv3/tools/export.py b/projects/PTv3/tools/export.py
index ae24c23b3..aea6848f9 100644
--- a/projects/PTv3/tools/export.py
+++ b/projects/PTv3/tools/export.py
@@ -11,6 +11,8 @@
 from models.utils.structure import Point, bit_length_tensor
 from torch.nn import functional as F
 
+from projects.SparseConvolution.sparse_functional import set_do_sort
+
 # NOTE: keep this import last; it overrides sparse conv registration for export.
 import SparseConvolution  # isort: skip
 
@@ -70,11 +72,19 @@ def forward(
         return pred_label, pred_probs
 
 
+def _apply_spconv_do_sort(cfg) -> None:
+    value = bool(cfg.get("spconv_do_sort", True))
+
+    set_do_sort(value)
+    print("[PTv3][export] spconv_do_sort=" f"{value} (baked into GetIndicePairsImplicitGemm.do_sort_i at ONNX export)")
+
+
 def main():
     args = default_argument_parser().parse_args()
     cfg = default_config_parser(args.config_file, args.options)
 
     cfg = default_setup(cfg)
+    _apply_spconv_do_sort(cfg)
     cfg.num_worker = 1
     cfg.num_worker_per_gpu = 1
 
diff --git a/projects/SparseConvolution/sparse_functional.py b/projects/SparseConvolution/sparse_functional.py
index efb72f7e1..528f83a72 100644
--- a/projects/SparseConvolution/sparse_functional.py
+++ b/projects/SparseConvolution/sparse_functional.py
@@ -6,7 +6,7 @@
 from cumm import tensorview as tv
 from spconv import constants
 from spconv.algo import CONV_CPP
-from spconv.constants import SPCONV_DO_SORT, SPCONV_USE_DIRECT_TABLE, AllocKeys
+from spconv.constants import SPCONV_USE_DIRECT_TABLE, AllocKeys
 from spconv.core import ConvAlgo
 from spconv.core_cc.csrc.sparse.all import SpconvOps
 from spconv.core_cc.csrc.sparse.convops.spops import ConvGemmOps
@@ -18,6 +18,14 @@
 from torch.onnx.symbolic_helper import _get_tensor_sizes
 
 
+def set_do_sort(value: bool) -> None:
+    """Set `do_sort` used by GetIndicePairsImplicitGemm symbolic/forward.
+
+    Kept as a module-level API so existing callers do not need to change.
+    """
+    GetIndicePairsImplicitGemm.set_do_sort(value)
+
+
 class GetIndicePairs(Function):
 
     @staticmethod
@@ -212,6 +220,12 @@ def backward(ctx: Any, grad_output: torch.Tensor) -> tuple:
 
 
 class GetIndicePairsImplicitGemm(Function):
+    # Controls `do_sort` in both ONNX symbolic and PyTorch forward paths.
+    _do_sort: bool = True
+
+    @classmethod
+    def set_do_sort(cls, value: bool) -> None:
+        cls._do_sort = bool(value)
 
     @staticmethod
     def symbolic(
@@ -245,6 +259,7 @@ def symbolic(
             subm_i=subm,
             transpose_i=transpose,
             is_train_i=is_train,
+            do_sort_i=int(GetIndicePairsImplicitGemm._do_sort),
             outputs=5,
         )
         indices_shape = _get_tensor_sizes(indices)
@@ -301,7 +316,7 @@ def forward(
 
         num_out_act_bound: int = -1
         direct_table: bool = SPCONV_USE_DIRECT_TABLE
-        do_sort = SPCONV_DO_SORT
+        do_sort = GetIndicePairsImplicitGemm._do_sort
 
         stream = get_current_stream()