diff --git a/SpineViewer/Models/UserStateModel.cs b/SpineViewer/Models/UserStateModel.cs
index f353a62..25eedaa 100644
--- a/SpineViewer/Models/UserStateModel.cs
+++ b/SpineViewer/Models/UserStateModel.cs
@@ -18,6 +18,7 @@ namespace SpineViewer.Models
         public double WindowHeight { get; set; }
         public WindowState WindowState { get; set; }
         
+        public bool RootGridCol0Folded { get; set; }
         public double RootGridCol0Width { get; set; }
         public double RootGridCol2Width { get; set; }
 
diff --git a/SpineViewer/Views/MainWindow.xaml.cs b/SpineViewer/Views/MainWindow.xaml.cs
index 26adac4..3d2fd34 100644
--- a/SpineViewer/Views/MainWindow.xaml.cs
+++ b/SpineViewer/Views/MainWindow.xaml.cs
@@ -49,6 +49,37 @@ public partial class MainWindow : Window
     private DispatcherTimer _saveUserStateTimer;
     private readonly TimeSpan _saveTimerDelay = TimeSpan.FromSeconds(3);
 
+    public bool RootGridCol0Folded
+    {
+        get => ((ContentPresenter)_mainTabControl.Template.FindName("PART_SelectedContentHost", _mainTabControl)).Visibility != Visibility.Visible;
+        set
+        {
+            var mainTabContentHost = (ContentPresenter)_mainTabControl.Template.FindName("PART_SelectedContentHost", _mainTabControl);
+            if ((mainTabContentHost.Visibility != Visibility.Visible) == value)
+                return;
+            if (value)
+            {
+                // 寄存折叠前的宽度比例
+                _rootGrid.ColumnDefinitions[0].Tag = _rootGrid.ColumnDefinitions[0].Width;
+                _rootGrid.ColumnDefinitions[1].Tag = _rootGrid.ColumnDefinitions[1].Width;
+                _rootGrid.ColumnDefinitions[2].Tag = _rootGrid.ColumnDefinitions[2].Width;
+
+                // 进行折叠
+                mainTabContentHost.Visibility = Visibility.Collapsed;
+                _rootGrid.ColumnDefinitions[0].Width = GridLength.Auto;
+                _rootGrid.ColumnDefinitions[1].Width = new(0);
+            }
+            else
+            {
+                // 解除折叠
+                _rootGrid.ColumnDefinitions[0].Width = (GridLength)_rootGrid.ColumnDefinitions[0].Tag;
+                _rootGrid.ColumnDefinitions[1].Width = (GridLength)_rootGrid.ColumnDefinitions[1].Tag;
+                _rootGrid.ColumnDefinitions[2].Width = (GridLength)_rootGrid.ColumnDefinitions[2].Tag;
+                mainTabContentHost.Visibility = Visibility.Visible;
+            }
+        }
+    }
+
     public MainWindow()
     {
         InitializeComponent();
@@ -231,8 +262,18 @@ public partial class MainWindow : Window
                 WindowState = WindowState.Normal;
             }
 
-            _rootGrid.ColumnDefinitions[0].Width = new(m.RootGridCol0Width, GridUnitType.Star);
-            _rootGrid.ColumnDefinitions[2].Width = new(m.RootGridCol2Width, GridUnitType.Star);
+            if (m.RootGridCol0Folded)
+            {
+                RootGridCol0Folded = true;
+                _rootGrid.ColumnDefinitions[0].Tag = new GridLength(m.RootGridCol0Width, GridUnitType.Star);
+                _rootGrid.ColumnDefinitions[2].Tag = new GridLength(m.RootGridCol2Width, GridUnitType.Star);
+            }
+            else
+            {
+                RootGridCol0Folded = false;
+                _rootGrid.ColumnDefinitions[0].Width = new(m.RootGridCol0Width, GridUnitType.Star);
+                _rootGrid.ColumnDefinitions[2].Width = new(m.RootGridCol2Width, GridUnitType.Star);
+            }
 
             _modelListGrid.RowDefinitions[0].Height = new(m.ModelListRow0Height, GridUnitType.Star);
             _modelListGrid.RowDefinitions[2].Height = new(m.ModelListRow2Height, GridUnitType.Star);
@@ -263,6 +304,7 @@ public partial class MainWindow : Window
             WindowHeight = rb.Height,
             WindowState = WindowState,
 
+            RootGridCol0Folded = RootGridCol0Folded,
             RootGridCol0Width = _rootGrid.ColumnDefinitions[0].Width.Value,
             RootGridCol2Width = _rootGrid.ColumnDefinitions[2].Width.Value,
 
@@ -284,6 +326,12 @@ public partial class MainWindow : Window
             BackgroundImageMode = _vm.SFMLRendererViewModel.BackgroundImageMode,
         };
 
+        if (m.RootGridCol0Folded)
+        {
+            m.RootGridCol0Width = ((GridLength)_rootGrid.ColumnDefinitions[0].Tag).Value;
+            m.RootGridCol2Width = ((GridLength)_rootGrid.ColumnDefinitions[2].Tag).Value;
+        }
+
         JsonHelper.Serialize(m, UserStateFilePath);
     }
 
@@ -387,6 +435,34 @@ public partial class MainWindow : Window
 
     #endregion
 
+    #region _mainTabControl 事件处理
+
+    private void MainTabControlHeader_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
+    {
+        // 全屏状态忽略该功能
+        if (_fullScreenLayout.Visibility == Visibility.Visible)
+            return;
+
+        if (sender is not FrameworkElement fe)
+            return;
+
+        // 找到包含这个 Border 的 TabItem
+        var tabItem = VisualFindParent<TabItem>(fe);
+        if (tabItem is null) 
+            return;
+
+        if (_mainTabControl.SelectedItem == tabItem)
+        {
+            RootGridCol0Folded = !RootGridCol0Folded;
+        }
+        else
+        {
+            RootGridCol0Folded = false;
+        }
+    }
+
+    #endregion
+
     #region _spinesListView 事件处理
 
     private void SpinesListView_RequestSelectionChanging(object? sender, NotifyCollectionChangedEventArgs e)
@@ -506,13 +582,6 @@ public partial class MainWindow : Window
         e.Handled = true;
     }
 
-    private static T? VisualUpwardSearch<T>(DependencyObject? source) where T : DependencyObject
-    {
-        while (source != null && source is not T)
-            source = VisualTreeHelper.GetParent(source);
-        return source as T;
-    }
-
     #endregion
 
     #region _spineFilesListBox 事件
@@ -553,6 +622,8 @@ public partial class MainWindow : Window
 
         if (_fullScreenLayout.Visibility == Visibility.Visible) return;
 
+        RootGridCol0Folded = false; // 取消折叠
+
         IntPtr hwnd = new WindowInteropHelper(this).Handle;
         if (User32.GetScreenResolution(hwnd, out var resX, out var resY))
         {
@@ -802,7 +873,16 @@ public partial class MainWindow : Window
     }
 
     #endregion
-    
+
+    private static T? VisualUpwardSearch<T>(DependencyObject? source) where T : DependencyObject
+    {
+        while (source != null && source is not T)
+            source = VisualTreeHelper.GetParent(source);
+        return source as T;
+    }
+
+    public static T? VisualFindParent<T>(DependencyObject child) where T : DependencyObject 
+        => VisualUpwardSearch<T>(VisualTreeHelper.GetParent(child));
 
     private void DebugMenuItem_Click(object sender, RoutedEventArgs e)
     {
@@ -812,9 +892,8 @@ public partial class MainWindow : Window
         _logger.Warn("Warn");
         _logger.Error("Error");
         _logger.Fatal("Fatal");
-        var _tabContentHost = (ContentPresenter?)_mainTabControl.Template.FindName("PART_SelectedContentHost", _mainTabControl);
-        _mainTabControl.Visibility = Visibility.Collapsed;
         return;
 #endif
     }
+
 }
\ No newline at end of file