diff --git a/lib/datasource/helm/index.ts b/lib/datasource/helm/index.ts
index 8552b09cb6bc7acf123d5e6a2a2646e37cb382ba..874e8bf162673ebcbbe416fe30093ecec37ad2e1 100644
--- a/lib/datasource/helm/index.ts
+++ b/lib/datasource/helm/index.ts
@@ -38,6 +38,11 @@ export async function getRepositoryData(
       logger.warn({ err }, `${repository} server error`);
       throw new Error(DATASOURCE_FAILURE);
     }
+    // istanbul ignore if
+    if (err.name === 'UnsupportedProtocolError') {
+      logger.info({ repository }, 'Unsupported protocol');
+      return null;
+    }
     logger.warn({ err }, `${repository} lookup failure: Unknown error`);
     return null;
   }