diff --git a/lib/datasource/docker.js b/lib/datasource/docker.js
index b2be4d11b509c01dde63543c11b991fae108c554..0099abf09089588dd76b9eabfaa1f934d550dc91 100644
--- a/lib/datasource/docker.js
+++ b/lib/datasource/docker.js
@@ -23,7 +23,7 @@ function massageRegistry(input) {
 }
 
 function getRepository(pkgName) {
-  return pkgName.includes('/') ? pkgName : `amd64/${pkgName}`;
+  return pkgName.includes('/') ? pkgName : `library/${pkgName}`;
 }
 
 async function getAuthHeaders(registry, repository) {