diff --git a/.github/workflows/X-x86_64_X.yml b/.github/workflows/X-x86_64_X.yml
index 6fafed8..7fb6a59 100644
--- a/.github/workflows/X-x86_64_X.yml
+++ b/.github/workflows/X-x86_64_X.yml
@@ -237,6 +237,7 @@ jobs:
 
 
     - name: Check Build Update
+      if: env.Result == 'true' && env.Release == 'true' && env.UPLOAD_RELEASES == 'true' && !cancelled()
       run: |
         export NOW_DATA_VERSION=${{env.NOW_DATA_VERSION}}
         export GITHUB_WORKSPACE=$GITHUB_WORKSPACE
diff --git a/.github/workflows/X-x86_64_Y.yml b/.github/workflows/X-x86_64_Y.yml
index 4026506..fc463fc 100644
--- a/.github/workflows/X-x86_64_Y.yml
+++ b/.github/workflows/X-x86_64_Y.yml
@@ -233,6 +233,7 @@ jobs:
 
 
     - name: Check Build Update
+      if: env.Result == 'true' && env.Release == 'true' && env.UPLOAD_RELEASES == 'true' && !cancelled()
       run: |
         export NOW_DATA_VERSION=${{env.NOW_DATA_VERSION}}
         export GITHUB_WORKSPACE=$GITHUB_WORKSPACE
diff --git a/.github/workflows/X-x86_64_Z.yml b/.github/workflows/X-x86_64_Z.yml
index 530f9c2..509f8aa 100644
--- a/.github/workflows/X-x86_64_Z.yml
+++ b/.github/workflows/X-x86_64_Z.yml
@@ -231,6 +231,7 @@ jobs:
         [ "${build_status}" == 0 ] && echo "Result=true" >> $GITHUB_ENV || echo "Result=false" >> $GITHUB_ENV
 
     - name: Check Build Update
+      if: env.Result == 'true' && env.Release == 'true' && env.UPLOAD_RELEASES == 'true' && !cancelled()
       run: |
         export NOW_DATA_VERSION=${{env.NOW_DATA_VERSION}}
         export GITHUB_WORKSPACE=$GITHUB_WORKSPACE
diff --git a/AI_CHANGELOG_BUILD_UPDATE_CONDITION.md b/AI_CHANGELOG_BUILD_UPDATE_CONDITION.md
new file mode 100644
index 0000000..483bb0f
--- /dev/null
+++ b/AI_CHANGELOG_BUILD_UPDATE_CONDITION.md
@@ -0,0 +1,12 @@
+# AI Modification Log: Build Update Condition
+
+Date: 2026-06-29
+
+## Change
+
+- Added an `if` condition to the `Check Build Update` step in X/Y/Z workflows.
+- The step now runs only when the build succeeded, release upload is enabled, and the workflow was not cancelled.
+
+## Reason
+
+The update checker depends on the build log and release metadata. Running it after a failed build or when release upload is disabled can cause unnecessary failures or remote API work.