diff --git a/docs/en/UI/AspNetCore/AutoComplete-Select.md b/docs/en/UI/AspNetCore/AutoComplete-Select.md
index 86d8c14b8a..e0ad7ceb24 100644
--- a/docs/en/UI/AspNetCore/AutoComplete-Select.md
+++ b/docs/en/UI/AspNetCore/AutoComplete-Select.md
@@ -22,7 +22,8 @@ A simple usage is presented below.
     data-autocomplete-display-property="name"
     data-autocomplete-value-property="id"
     data-autocomplete-items-property="items"
-    data-autocomplete-filter-param-name="filter">
+    data-autocomplete-filter-param-name="filter"
+    data-autocomplete-allow-clear="true">
 
     <!-- You can define selected option(s) here  -->
     <option selected value="@SelectedAuthor.Id">@SelectedAuthor.Name</option>
@@ -38,6 +39,8 @@ The select must have the `auto-complete-select` class and the following attribut
 - `data-autocomplete-filter-param-name`: * Filter text property name. _(For example: `filter`)_.
 - `data-autocomplete-selected-item-name`: Text to display as selected item.
 - `data-autocomplete-parent-selector`: jQuery selector expression for parent DOM. _(If it's in a modal, it's suggested to send the modal selector as this parameter)_.
+- `data-autocomplete-allow-clear`: If `true`, it'll allow to clear the selected value. Default value: `false`.
+- `data-autocomplete-placeholder`: Placeholder text to display when no value is selected.
 
 Also, selected value(s) should be defined with the `<option>` tags inside select, since pagination is applied and the selected options might haven't loaded yet.
 
diff --git a/framework/src/Volo.Abp.AspNetCore.Mvc.UI.Bootstrap/TagHelpers/Form/AbpSelectTagHelper.cs b/framework/src/Volo.Abp.AspNetCore.Mvc.UI.Bootstrap/TagHelpers/Form/AbpSelectTagHelper.cs
index 75ae03115a..58c7b1b45d 100644
--- a/framework/src/Volo.Abp.AspNetCore.Mvc.UI.Bootstrap/TagHelpers/Form/AbpSelectTagHelper.cs
+++ b/framework/src/Volo.Abp.AspNetCore.Mvc.UI.Bootstrap/TagHelpers/Form/AbpSelectTagHelper.cs
@@ -38,6 +38,10 @@ public class AbpSelectTagHelper : AbpTagHelper<AbpSelectTagHelper, AbpSelectTagH
 
     public string AutocompleteSelectedItemValue { get; set; }
 
+    public string AllowClear { get; set; }
+
+    public string Placeholder { get; set; }
+
     public AbpSelectTagHelper(AbpSelectTagHelperService tagHelperService)
         : base(tagHelperService)
     {
diff --git a/framework/src/Volo.Abp.AspNetCore.Mvc.UI.Bootstrap/TagHelpers/Form/AbpSelectTagHelperService.cs b/framework/src/Volo.Abp.AspNetCore.Mvc.UI.Bootstrap/TagHelpers/Form/AbpSelectTagHelperService.cs
index 45368b2dda..350898d41d 100644
--- a/framework/src/Volo.Abp.AspNetCore.Mvc.UI.Bootstrap/TagHelpers/Form/AbpSelectTagHelperService.cs
+++ b/framework/src/Volo.Abp.AspNetCore.Mvc.UI.Bootstrap/TagHelpers/Form/AbpSelectTagHelperService.cs
@@ -120,6 +120,8 @@ public class AbpSelectTagHelperService : AbpTagHelperService<AbpSelectTagHelper>
             output.Attributes.Add("data-autocomplete-filter-param-name", TagHelper.AutocompleteFilterParamName);
             output.Attributes.Add("data-autocomplete-selected-item-name", TagHelper.AutocompleteSelectedItemName);
             output.Attributes.Add("data-autocomplete-selected-item-value", TagHelper.AutocompleteSelectedItemValue);
+            output.Attributes.Add("data-autocomplete-allow-clear", TagHelper.AllowClear);
+            output.Attributes.Add("data-autocomplete-placeholder", TagHelper.Placeholder);
         }
     }
 
diff --git a/framework/src/Volo.Abp.AspNetCore.Mvc.UI.Theme.Shared/wwwroot/libs/abp/aspnetcore-mvc-ui-theme-shared/bootstrap/dom-event-handlers.js b/framework/src/Volo.Abp.AspNetCore.Mvc.UI.Theme.Shared/wwwroot/libs/abp/aspnetcore-mvc-ui-theme-shared/bootstrap/dom-event-handlers.js
index 009c32d253..d1cbfa6b6b 100644
--- a/framework/src/Volo.Abp.AspNetCore.Mvc.UI.Theme.Shared/wwwroot/libs/abp/aspnetcore-mvc-ui-theme-shared/bootstrap/dom-event-handlers.js
+++ b/framework/src/Volo.Abp.AspNetCore.Mvc.UI.Theme.Shared/wwwroot/libs/abp/aspnetcore-mvc-ui-theme-shared/bootstrap/dom-event-handlers.js
@@ -74,20 +74,26 @@
     abp.dom.initializers.initializeAutocompleteSelects = function ($autocompleteSelects) {
         if ($autocompleteSelects.length) {
             $autocompleteSelects.each(function () {
-                var $select = $(this);
-                var url = $(this).data("autocompleteApiUrl");
-                var displayName = $(this).data("autocompleteDisplayProperty");
-                var displayValue = $(this).data("autocompleteValueProperty");
-                var itemsPropertyName = $(this).data("autocompleteItemsProperty");
-                var filterParamName = $(this).data("autocompleteFilterParamName");
-                var selectedText = $(this).data("autocompleteSelectedItemName");
-                var parentSelector = $(this).data("autocompleteParentSelector");
-                if(!parentSelector && $select.parents(".modal.fade").length === 1){
+                let $select = $(this);
+                let url = $(this).data("autocompleteApiUrl");
+                let displayName = $(this).data("autocompleteDisplayProperty");
+                let displayValue = $(this).data("autocompleteValueProperty");
+                let itemsPropertyName = $(this).data("autocompleteItemsProperty");
+                let filterParamName = $(this).data("autocompleteFilterParamName");
+                let selectedText = $(this).data("autocompleteSelectedItemName");
+                let parentSelector = $(this).data("autocompleteParentSelector");
+                let allowClear = $(this).data("autocompleteAllowClear");
+                let placeholder = $(this).data("autocompletePlaceholder");
+                if (allowClear && placeholder == undefined) {
+                    placeholder = " ";
+                }
+
+                if (!parentSelector && $select.parents(".modal.fade").length === 1) {
                     parentSelector = ".modal.fade";
                 }
-                var name = $(this).attr("name");
-                var selectedTextInputName = name + "_Text";
-                var selectedTextInput = $('<input>', {
+                let name = $(this).attr("name");
+                let selectedTextInputName = name + "_Text";
+                let selectedTextInput = $('<input>', {
                     type: 'hidden',
                     id: selectedTextInputName,
                     name: selectedTextInputName,
@@ -101,13 +107,13 @@
                         url: url,
                         dataType: "json",
                         data: function (params) {
-                            var query = {};
+                            let query = {};
                             query[filterParamName] = params.term;
                             return query;
                         },
                         processResults: function (data) {
-                            var retVal = [];
-                            var items = data;
+                            let retVal = [];
+                            let items = data;
                             if (itemsPropertyName) {
                                 items = data[itemsPropertyName];
                             }
@@ -125,6 +131,11 @@
                     },
                     width: '100%',
                     dropdownParent: parentSelector ? $(parentSelector) : $('body'),
+                    allowClear: allowClear,
+                    placeholder: {
+                        id: '-1',
+                        text: placeholder
+                    }
                 });
                 $select.on('select2:select', function (e) {
                     selectedTextInput.val(e.params.data.text);
diff --git a/npm/ng-packs/angular.json b/npm/ng-packs/angular.json
index 0b2e115734..cd9029142c 100644
--- a/npm/ng-packs/angular.json
+++ b/npm/ng-packs/angular.json
@@ -277,6 +277,11 @@
                 "inject": true,
                 "bundleName": "ngx-datatable-material"
               },
+              {
+                "input": "node_modules/ng-zorro-antd/tree/style/index.min.css",
+                "inject": false,
+                "bundleName": "ng-zorro-antd-tree"
+              },
               "apps/dev-app/src/styles.scss"
             ],
             "scripts": []
diff --git a/npm/ng-packs/packages/components/tree/src/lib/components/tree.component.ts b/npm/ng-packs/packages/components/tree/src/lib/components/tree.component.ts
index 0dcd29113d..e7566c587d 100644
--- a/npm/ng-packs/packages/components/tree/src/lib/components/tree.component.ts
+++ b/npm/ng-packs/packages/components/tree/src/lib/components/tree.component.ts
@@ -2,10 +2,13 @@ import {
   Component,
   ContentChild,
   EventEmitter,
+  Inject,
   Input,
+  Optional,
   Output,
   TemplateRef,
   ViewEncapsulation,
+  OnInit
 } from '@angular/core';
 import { NzFormatBeforeDropEvent, NzFormatEmitEvent } from 'ng-zorro-antd/tree';
 import { of } from 'rxjs';
@@ -13,6 +16,7 @@ import { TreeNodeTemplateDirective } from '../templates/tree-node-template.direc
 import { ExpandedIconTemplateDirective } from '../templates/expanded-icon-template.directive';
 import { NgbDropdown } from '@ng-bootstrap/ng-bootstrap';
 import { LazyLoadService, LOADING_STRATEGY, SubscriptionService } from '@abp/ng.core';
+import { DISABLE_TREE_STYLE_LOADING_TOKEN } from '../disable-tree-style-loading.token';
 
 export type DropEvent = NzFormatEmitEvent & { pos: number };
 
@@ -23,16 +27,18 @@ export type DropEvent = NzFormatEmitEvent & { pos: number };
   encapsulation: ViewEncapsulation.None,
   providers: [SubscriptionService],
 })
-export class TreeComponent {
+export class TreeComponent implements OnInit {
   dropPosition: number;
 
   dropdowns = {} as { [key: string]: NgbDropdown };
-  constructor(private lazyLoadService: LazyLoadService, subscriptionService: SubscriptionService) {
-    const loaded$ = this.lazyLoadService.load(
-      LOADING_STRATEGY.AppendAnonymousStyleToHead('ng-zorro-antd-tree.css'),
-    );
-    subscriptionService.addOne(loaded$);
-  }
+
+  constructor(
+    private lazyLoadService: LazyLoadService,
+    subscriptionService: SubscriptionService,
+    @Optional()
+    @Inject(DISABLE_TREE_STYLE_LOADING_TOKEN)
+    private disableTreeStyleLoading: boolean | undefined,
+  ) { }
 
   @ContentChild('menu') menu: TemplateRef<any>;
   @ContentChild(TreeNodeTemplateDirective) customNodeTemplate: TreeNodeTemplateDirective;
@@ -57,6 +63,20 @@ export class TreeComponent {
     return of(false);
   };
 
+  ngOnInit() {
+    this.loadStyle()
+  }
+
+  private loadStyle() {
+    if (disableTreeStyleLoading) {
+      return;
+    }
+    const loaded$ = this.lazyLoadService.load(
+      LOADING_STRATEGY.AppendAnonymousStyleToHead('ng-zorro-antd-tree.css'),
+    );
+    subscriptionService.addOne(loaded$);
+  }
+  
   onSelectedNodeChange(node) {
     this.selectedNode = node.origin.entity;
     if (this.changeCheckboxWithNode) {
diff --git a/npm/ng-packs/packages/components/tree/src/lib/disable-tree-style-loading.token.ts b/npm/ng-packs/packages/components/tree/src/lib/disable-tree-style-loading.token.ts
new file mode 100644
index 0000000000..a96f7cb235
--- /dev/null
+++ b/npm/ng-packs/packages/components/tree/src/lib/disable-tree-style-loading.token.ts
@@ -0,0 +1,5 @@
+import { InjectionToken } from '@angular/core';
+
+export const DISABLE_TREE_STYLE_LOADING_TOKEN = new InjectionToken<boolean>(
+  'DISABLE_TREE_STYLE_LOADING_TOKEN',
+);
diff --git a/npm/ng-packs/packages/components/tree/src/public-api.ts b/npm/ng-packs/packages/components/tree/src/public-api.ts
index 1f3dd48e00..9b5caf5976 100644
--- a/npm/ng-packs/packages/components/tree/src/public-api.ts
+++ b/npm/ng-packs/packages/components/tree/src/public-api.ts
@@ -3,3 +3,4 @@ export * from './lib/components/tree.component';
 export * from './lib/utils/nz-tree-adapter';
 export * from './lib/templates/tree-node-template.directive';
 export * from './lib/templates/expanded-icon-template.directive';
+export * from './lib/disable-tree-style-loading.token';