diff --git a/.azure-pipelines/Windows-CI.yml b/.azure-pipelines/Windows-CI.yml
index 8303fee5aa..bcb91f9f71 100644
--- a/.azure-pipelines/Windows-CI.yml
+++ b/.azure-pipelines/Windows-CI.yml
@@ -11,8 +11,8 @@ parameters:
 
 jobs:
 - job: Build_onnx_mlir_Windows
-  # 4h timeout is sometimes a tiny bit short when llvm-project is rebuilt
-  timeoutInMinutes: 270
+  # Sometimes takes more than 4.5h when llvm-project is rebuilt
+  timeoutInMinutes: 330
   pool:
     vmImage: 'windows-2019'