diff --git a/v2rayN/v2rayN.Desktop/ViewModels/ThemeSettingViewModel.cs b/v2rayN/v2rayN.Desktop/ViewModels/ThemeSettingViewModel.cs
index 63759525..d0854a2f 100644
--- a/v2rayN/v2rayN.Desktop/ViewModels/ThemeSettingViewModel.cs
+++ b/v2rayN/v2rayN.Desktop/ViewModels/ThemeSettingViewModel.cs
@@ -103,6 +103,8 @@ namespace v2rayN.Desktop.ViewModels
         private void ModifyFontSize()
         {
             double size = CurrentFontSize;
+            if (size < Global.MinFontSize) return;
+
             Style style = new(x => Selectors.Or(
                 x.OfType<Button>(),
                 x.OfType<TextBox>(),
diff --git a/v2rayN/v2rayN/ViewModels/ThemeSettingViewModel.cs b/v2rayN/v2rayN/ViewModels/ThemeSettingViewModel.cs
index 2050d8e5..22eb78ed 100644
--- a/v2rayN/v2rayN/ViewModels/ThemeSettingViewModel.cs
+++ b/v2rayN/v2rayN/ViewModels/ThemeSettingViewModel.cs
@@ -158,7 +158,7 @@ namespace v2rayN.ViewModels
         private void ModifyFontSize()
         {
             double size = (long)CurrentFontSize;
-            if (size < Global.MinFontSize) size = Global.MinFontSize;
+            if (size < Global.MinFontSize) return;
 
             Application.Current.Resources["StdFontSize"] = size;
             Application.Current.Resources["StdFontSize1"] = size + 1;