diff --git a/onnxscript/function_libs/torch_lib/_flags.py b/onnxscript/function_libs/torch_lib/_flags.py
index f3645ecae..fcdc00f32 100644
--- a/onnxscript/function_libs/torch_lib/_flags.py
+++ b/onnxscript/function_libs/torch_lib/_flags.py
@@ -54,4 +54,5 @@ def _load_boolean_flag(
 EXPERIMENTAL_USE_IR: bool = _load_boolean_flag(
     "TORCHLIB_EXPERIMENTAL_USE_IR",
     this_will="use the ONNX IR instead of the PyTorch Graph for graph building",
+    deprecated=True,
 )