diff --git a/src/AtomUI.Desktop.Controls/TabControl/CardTabControl.cs b/src/AtomUI.Desktop.Controls/TabControl/CardTabControl.cs
index 16a21e7ec..f55d9dc16 100644
--- a/src/AtomUI.Desktop.Controls/TabControl/CardTabControl.cs
+++ b/src/AtomUI.Desktop.Controls/TabControl/CardTabControl.cs
@@ -5,6 +5,7 @@ using Avalonia;
 using Avalonia.Controls;
 using Avalonia.Controls.Presenters;
 using Avalonia.Controls.Primitives;
+using Avalonia.Data;
 using Avalonia.Interactivity;
 using Avalonia.Layout;
 
@@ -97,7 +98,8 @@ public class CardTabControl : BaseTabControl
             Debug.Assert(ItemsBindingDisposables.ContainsKey(tabItem));
             var disposables = ItemsBindingDisposables[tabItem];
             disposables.Add(BindUtils.RelayBind(this, EffectiveCardBorderRadiusProperty, tabItem, TabItem.CornerRadiusProperty));
-            disposables.Add(BindUtils.RelayBind(this, CardBorderThicknessProperty, tabItem, TabItem.BorderThicknessProperty));
+            // Use template-level priority so selected-state styles can override border thickness
+            disposables.Add(BindUtils.RelayBind(this, CardBorderThicknessProperty, tabItem, TabItem.BorderThicknessProperty, BindingMode.Default, BindingPriority.Template));
         }
     }
 
@@ -185,4 +187,4 @@ public class CardTabControl : BaseTabControl
             }
         }
     }
-}
\ No newline at end of file
+}
diff --git a/src/AtomUI.Desktop.Controls/TabControl/Themes/CardTabItemTheme.axaml b/src/AtomUI.Desktop.Controls/TabControl/Themes/CardTabItemTheme.axaml
index 99d386a45..ae9fe3807 100644
--- a/src/AtomUI.Desktop.Controls/TabControl/Themes/CardTabItemTheme.axaml
+++ b/src/AtomUI.Desktop.Controls/TabControl/Themes/CardTabItemTheme.axaml
@@ -36,10 +36,25 @@
         <Setter Property="Margin" Value="{DynamicResource {x:Static atom:TabControlTokenKey.HorizontalItemMargin}}" />
         <Setter Property="Background" Value="{DynamicResource {x:Static atom:TabControlTokenKey.CardBg}}" />
         <Setter Property="BorderBrush" Value="{DynamicResource {x:Static atom:SharedTokenKey.ColorBorderSecondary}}" />
+        <Setter Property="BorderThickness" Value="{DynamicResource {x:Static atom:SharedTokenKey.BorderThickness}}" />
 
         <Style Selector="^:selected">
             <Setter Property="Background" Value="{DynamicResource {x:Static atom:SharedTokenKey.ColorBgContainer}}" />
         </Style>
+        <!-- 选中态按放置方向去掉靠内容侧的边框 -->
+        <Style Selector="^[TabStripPlacement=Top]:selected">
+            <Setter Property="BorderThickness" Value="1,1,1,0" />
+        </Style>
+        <Style Selector="^[TabStripPlacement=Bottom]:selected">
+            <Setter Property="BorderThickness" Value="1,0,1,1" />
+        </Style>
+        <Style Selector="^[TabStripPlacement=Left]:selected">
+            <Setter Property="BorderThickness" Value="1,1,0,1" />
+        </Style>
+        <Style Selector="^[TabStripPlacement=Right]:selected">
+            <Setter Property="BorderThickness" Value="0,1,1,1" />
+        </Style>
+
 
         <Style Selector="^[TabStripPlacement=Top], ^[TabStripPlacement=Bottom]">
             <Setter Property="Margin" Value="{DynamicResource {x:Static atom:TabControlTokenKey.HorizontalItemMargin}}" />
@@ -104,4 +119,4 @@
         </Style>
 
     </ControlTheme>
-</ResourceDictionary>
\ No newline at end of file
+</ResourceDictionary>