diff --git a/packages/@vuepress/theme-default/components/SidebarLink.vue b/packages/@vuepress/theme-default/components/SidebarLink.vue
index 7d128b4a98..243ce7630b 100644
--- a/packages/@vuepress/theme-default/components/SidebarLink.vue
+++ b/packages/@vuepress/theme-default/components/SidebarLink.vue
@@ -28,7 +28,9 @@ export default {
     const active = item.type === 'auto'
       ? selfActive || item.children.some(c => isActive($route, item.basePath + '#' + c.slug))
       : selfActive
-    const link = renderLink(h, item.path, item.title || item.path, active)
+    const link = item.type === 'external'
+      ? renderExternal(h, item.path, item.title || item.path)
+      : renderLink(h, item.path, item.title || item.path, active)
 
     const configDepth = $page.frontmatter.sidebarDepth
       || sidebarDepth
@@ -75,6 +77,19 @@ function renderChildren (h, children, path, route, maxDepth, depth = 1) {
     ])
   }))
 }
+
+function renderExternal (h, to, text) {
+  return h('a', {
+    attrs: {
+      href: to,
+      target: '_blank',
+      rel: 'noopener noreferrer'
+    },
+    class: {
+      'sidebar-link': true
+    }
+  }, [text, h('OutboundLink')])
+}
 </script>
 
 <style lang="stylus">
diff --git a/packages/@vuepress/theme-default/util/index.js b/packages/@vuepress/theme-default/util/index.js
index 9913ff7ea4..865d6c6f3f 100644
--- a/packages/@vuepress/theme-default/util/index.js
+++ b/packages/@vuepress/theme-default/util/index.js
@@ -54,6 +54,13 @@ export function isActive (route, path) {
 }
 
 export function resolvePage (pages, rawPath, base) {
+  if (isExternal(rawPath)) {
+    return {
+      type: 'external',
+      title: rawPath,
+      path: rawPath
+    }
+  }
   if (base) {
     rawPath = resolvePath(rawPath, base)
   }