diff --git a/public/app/plugins/datasource/cloud-monitoring/datasource.ts b/public/app/plugins/datasource/cloud-monitoring/datasource.ts
index 17699efbab6..e0baaa151c7 100644
--- a/public/app/plugins/datasource/cloud-monitoring/datasource.ts
+++ b/public/app/plugins/datasource/cloud-monitoring/datasource.ts
@@ -62,7 +62,7 @@ export default class CloudMonitoringDatasource extends DataSourceWithBackend<
         metricType: this.templateSrv.replace(annotation.target.metricType, options.scopedVars || {}),
         title: this.templateSrv.replace(annotation.target.title, options.scopedVars || {}),
         text: this.templateSrv.replace(annotation.target.text, options.scopedVars || {}),
-        tags: this.templateSrv.replace(annotation.target.tags, options.scopedVars || {}),
+        tags: (annotation.target.tags || []).map((t: string) => this.templateSrv.replace(t, options.scopedVars || {})),
         projectName: this.templateSrv.replace(
           annotation.target.projectName ? annotation.target.projectName : this.getDefaultProject(),
           options.scopedVars || {}