diff --git a/.github/workflows/build.yaml b/.github/workflows/build.yaml
index 710bef0..2ed2cc0 100644
--- a/.github/workflows/build.yaml
+++ b/.github/workflows/build.yaml
@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     env:
       REGISTRY: ghcr.io
-      IMAGE: "${{ github.repository }}:${{ github.sha }}"
+      IMAGE: "ghcr.io/${{ github.repository }}:${{ github.sha }}"
     # このリポジトリに対する書き込み権限を付与
     permissions:
       contents: write