diff --git a/Windows/CS/Framework4.0/Toprie/Toprie/Setting.cs b/Windows/CS/Framework4.0/Toprie/Toprie/Setting.cs
index 1a30747..34f5bea 100644
--- a/Windows/CS/Framework4.0/Toprie/Toprie/Setting.cs
+++ b/Windows/CS/Framework4.0/Toprie/Toprie/Setting.cs
@@ -652,8 +652,10 @@ namespace JoyD.Windows.CS
                 // 获取相对于图像的坐标作为矩形起始点
                 Point imagePoint = ControlPointToImagePoint(e.Location);
                 
-                // 按下鼠标时初始框大小即为笔块大小
-                _rectangleStartPoint = imagePoint;
+                // 按下鼠标时初始框以鼠标位置为中心，大小为画笔大小
+                // 计算初始矩形的左上角和右下角（以鼠标位置为中心，减去和加上画笔一半宽高）
+                int halfBrushSize = _currentBrushSize / 2;
+                _rectangleStartPoint = new Point(imagePoint.X - halfBrushSize, imagePoint.Y - halfBrushSize);
                 _isDrawingRectangle = true;
                 return;
             }
@@ -1270,11 +1272,14 @@ namespace JoyD.Windows.CS
                     // 获取相对于图像的当前坐标
                     Point currentImagePoint = ControlPointToImagePoint(e.Location);
                     
-                    // 计算矩形参数：左上点是起笔方块的左上点，右下点是收笔方块的右下点
+                    // 计算矩形参数：左上点是起笔方块的左上点，右下点是当前鼠标位置+画笔一半的宽高
+                    int halfBrushSize = _currentBrushSize / 2;
                     int x = _rectangleStartPoint.X;
                     int y = _rectangleStartPoint.Y;
-                    int width = currentImagePoint.X - _rectangleStartPoint.X;
-                    int height = currentImagePoint.Y - _rectangleStartPoint.Y;
+                    // 右下角为当前鼠标位置+画笔一半的宽高
+                    Point endPoint = new Point(currentImagePoint.X + halfBrushSize, currentImagePoint.Y + halfBrushSize);
+                    int width = endPoint.X - x;
+                    int height = endPoint.Y - y;
                     
                     // 确保矩形大小为正数，调整起点和大小
                     if (width < 0)
@@ -1751,11 +1756,14 @@ namespace JoyD.Windows.CS
                         // 获取相对于图像的当前坐标
                         Point currentImagePoint = ControlPointToImagePoint(e.Location);
                         
-                        // 计算矩形参数：左上点是起笔方块的左上点，右下点是收笔方块的右下点
+                        // 计算矩形参数：左上点是起笔方块的左上点，右下点是当前鼠标位置+画笔一半的宽高
+                        int halfBrushSize = _currentBrushSize / 2;
                         int x = _rectangleStartPoint.X;
                         int y = _rectangleStartPoint.Y;
-                        int width = currentImagePoint.X - _rectangleStartPoint.X;
-                        int height = currentImagePoint.Y - _rectangleStartPoint.Y;
+                        // 右下角为当前鼠标位置+画笔一半的宽高
+                        Point endPoint = new Point(currentImagePoint.X + halfBrushSize, currentImagePoint.Y + halfBrushSize);
+                        int width = endPoint.X - x;
+                        int height = endPoint.Y - y;
                         
                         // 确保矩形大小为正数，调整起点和大小
                         if (width < 0)