diff --git a/packages/@vuepress/core/lib/app/components/Content.js b/packages/@vuepress/core/lib/app/components/Content.js
index <HASH>..<HASH> 100644
--- a/packages/@vuepress/core/lib/app/components/Content.js
+++ b/packages/@vuepress/core/lib/app/components/Content.js
@@ -13,7 +13,7 @@ export default {
     if (Vue.$vuepress.isPageExists(pageKey)) {
       // In SSR, if a component is not registered with the component option
       // vue-server-renderer will not be able to resovle it.
-      if (!parent.$ssrContext) {
+      if (!this.$parent.$ssrContext) {
         Vue.$vuepress.registerPageAsyncComponent(pageKey)
       }
fix($core): variable `parent` is undefined in build process (#<I>)