diff --git a/.github/workflows/ios.yml b/.github/workflows/ios.yml
index 91c04cd..dd03b4e 100644
--- a/.github/workflows/ios.yml
+++ b/.github/workflows/ios.yml
@@ -31,9 +31,6 @@ jobs:
           path: libmozc/mozc
           ref: ${{ inputs.mozc_sha }}
 
-      - name: Patch protobuf to accelerate build
-        run: git apply --directory=libmozc/mozc/src/third_party/protobuf libmozc/patches/protobuf.patch
-
       - uses: actions/setup-python@v5
         with:
           python-version: '3.12'
diff --git a/.github/workflows/js.yml b/.github/workflows/js.yml
index 391e938..cdf2ea1 100644
--- a/.github/workflows/js.yml
+++ b/.github/workflows/js.yml
@@ -25,9 +25,6 @@ jobs:
           path: libmozc/mozc
           ref: ${{ inputs.mozc_sha }}
 
-      - name: Patch protobuf to accelerate build
-        run: git apply --directory=libmozc/mozc/src/third_party/protobuf libmozc/patches/protobuf.patch
-
       - uses: actions/setup-python@v5
         with:
           python-version: '3.12'
diff --git a/.github/workflows/macos.yml b/.github/workflows/macos.yml
index eb09639..cc9f841 100644
--- a/.github/workflows/macos.yml
+++ b/.github/workflows/macos.yml
@@ -31,9 +31,6 @@ jobs:
           path: libmozc/mozc
           ref: ${{ inputs.mozc_sha }}
 
-      - name: Patch protobuf to accelerate build
-        run: git apply --directory=libmozc/mozc/src/third_party/protobuf libmozc/patches/protobuf.patch
-
       - uses: actions/setup-python@v5
         with:
           python-version: '3.12'