diff --git a/modules/docs/src/Volo.Docs.Application.Contracts/Volo/Docs/Documents/ContentWithDetailsDto.cs b/modules/docs/src/Volo.Docs.Application.Contracts/Volo/Docs/Documents/ContentWithDetailsDto.cs
index 9d9dcc63ba..067ad5e759 100644
--- a/modules/docs/src/Volo.Docs.Application.Contracts/Volo/Docs/Documents/ContentWithDetailsDto.cs
+++ b/modules/docs/src/Volo.Docs.Application.Contracts/Volo/Docs/Documents/ContentWithDetailsDto.cs
@@ -42,6 +42,31 @@ namespace Volo.Docs.Documents
         public bool HasChildItems => Items != null && Items.Any();
 
         public bool IsEmpty => Text == null && Path == null;
+
+        public bool IsOpened(string documentName)
+        {
+            if (documentName == null)
+            {
+                return false;
+            }
+
+            if (!HasChildItems)
+            {
+                return documentName == Path;
+            }
+
+            var isOpened = false;
+            foreach (var n in Items)
+            {
+                if (n.IsOpened(documentName))
+                {
+                    isOpened = true;
+                    break;
+                }
+            }
+
+            return isOpened;
+        }
     }
 
     public class NavigationWithDetailsDto : DocumentWithDetailsDto
diff --git a/modules/docs/src/Volo.Docs.Web/Areas/Documents/Helpers/TagHelpers/TreeTagHelper.cs b/modules/docs/src/Volo.Docs.Web/Areas/Documents/Helpers/TagHelpers/TreeTagHelper.cs
index d1febd8b5b..1f38c22a78 100644
--- a/modules/docs/src/Volo.Docs.Web/Areas/Documents/Helpers/TagHelpers/TreeTagHelper.cs
+++ b/modules/docs/src/Volo.Docs.Web/Areas/Documents/Helpers/TagHelpers/TreeTagHelper.cs
@@ -1,4 +1,5 @@
 using System;
+using System.Linq;
 using System.Text;
 using Microsoft.AspNetCore.Razor.TagHelpers;
 using Volo.Docs.Documents;
@@ -15,9 +16,10 @@ namespace Volo.Docs.Areas.Documents.Helpers.TagHelpers
                                                       </span>
                                                   </label>
                                                   <a href='{0}' class='{5}'>{1}</a>
-                                                {2}</li>";
+                                                  {2}
+                                              </li>";
 
-        private const string UlItemTemplate = @"<ul class='nav nav-list tree'>
+        private const string UlItemTemplate = @"<ul class='nav nav-list tree' style='{1}'>
                                                     {0}
                                                 </ul>";
 
@@ -30,45 +32,60 @@ namespace Volo.Docs.Areas.Documents.Helpers.TagHelpers
         [HtmlAttributeName("project-name")]
         public string ProjectName { get; set; }
 
+        [HtmlAttributeName("selected-document-name")]
+        public string SelectedDocumentName { get; set; }
+
         public override void Process(TagHelperContext context, TagHelperOutput output)
         {
             var content = new StringBuilder();
+
             RootNode.Items?.ForEach(childNode =>
-                {
-                    content.Append(RenderTreeNodeAsHtml(childNode));
-                });
+            {
+                content.Append(RenderNodeAsHtml(childNode));
+            });
 
             output.Content.AppendHtml(content.ToString());
         }
 
-        private string RenderTreeNodeAsHtml(NavigationNode node)
+        private string RenderNodeAsHtml(NavigationNode node)
         {
             var content = "";
 
+            var isAnyNodeOpenedInThisLevel = node.Items?.Any(n => n.IsOpened(SelectedDocumentName)) ?? false;
+
             node.Items?.ForEach(innerNode =>
             {
-                content += GetParentNode(innerNode);
+                content += GetParentNode(innerNode, isAnyNodeOpenedInThisLevel);
             });
 
-            return node.IsEmpty ?
-                content :
-                GetLeafNode(node, content);
+            var result = node.IsEmpty ? content : GetLeafNode(node, content);
+
+            return result;
         }
 
-        private string GetParentNode(NavigationNode node)
+        private string GetParentNode(NavigationNode node, bool isOpened)
         {
-            return string.Format(UlItemTemplate, RenderTreeNodeAsHtml(node));
+            var output = RenderNodeAsHtml(node);
+
+            return string.Format(UlItemTemplate, output, isOpened ? "" : "display: none;");
         }
 
         private string GetLeafNode(NavigationNode node, string content)
         {
+            var cssClass = node.Path.IsNullOrEmpty() ? "tree-toggle" : "";
+
+            if (node.IsOpened(SelectedDocumentName))
+            {
+                cssClass += " opened";
+            }
+
             return string.Format(LiItemTemplate,
                 node.Path.IsNullOrEmpty() ? "#" : "/documents/" + ProjectName + "/" + Version + "/" + node.Path,
                 node.Text.IsNullOrEmpty() ? "?" : node.Text,
                 content,
                 node.HasChildItems ? "nav-header" : "last-link",
                 node.HasChildItems ? "chevron-down" : "long-arrow-right",
-                node.Path.IsNullOrEmpty() ? "tree-toggle" : "");
+                cssClass);
         }
 
     }
diff --git a/modules/docs/src/Volo.Docs.Web/Pages/Documents/Project/Index.cshtml b/modules/docs/src/Volo.Docs.Web/Pages/Documents/Project/Index.cshtml
index 1602c00ec2..0251b1c323 100644
--- a/modules/docs/src/Volo.Docs.Web/Pages/Documents/Project/Index.cshtml
+++ b/modules/docs/src/Volo.Docs.Web/Pages/Documents/Project/Index.cshtml
@@ -79,6 +79,7 @@
                     <ul root-node="@Model.Navigation.RootNode"
                         version="@(Model.Version.IsNullOrEmpty() ? "latest" : Model.Version)"
                         project-name="@Model.ProjectName"
+                        selected-document-name="@Model.DocumentName"
                         id="sidebar-scroll"
                         class="nav nav-list"></ul>
                 </div>
diff --git a/modules/docs/src/Volo.Docs.Web/Pages/Documents/vs.js b/modules/docs/src/Volo.Docs.Web/Pages/Documents/vs.js
index 70ac87204f..01553608d8 100644
--- a/modules/docs/src/Volo.Docs.Web/Pages/Documents/vs.js
+++ b/modules/docs/src/Volo.Docs.Web/Pages/Documents/vs.js
@@ -2,10 +2,6 @@ $('.tree-toggle').click(function () {
     $(this).parent().children('ul.tree').toggle(100);
     $(this).toggleClass("opened");
 });
-$(function () {
-    $('.tree-toggle').parent().children('ul.tree').toggle(100);
-})
-
 
 $(document).ready(function () {
     var scrollTopBtn = $(".scroll-top-btn");
@@ -35,6 +31,7 @@ function handleSidebar() {
     var sideBar = $(".docs-sidebar-wrapper");
     sideBar.css("margin-left", sideBarPosition);
 }
+
 $(window).resize(function () {
     handleSidebar();
 });
@@ -75,15 +72,18 @@ $('.open-dmenu').on("click", function () {
 
 
 (function ($) {
+
     $(window).on("load", function () {
         $("#sidebar-scroll").mCustomScrollbar({
             theme: "minimal"
         });
     });
+
     $(window).on("load", function () {
         $("#index-scroll").mCustomScrollbar({
             theme: "minimal-dark"
         });
     });
+
 })(jQuery);