diff --git a/tools/services/font_service.py b/tools/services/font_service.py
index 43721a9..9312a03 100644
--- a/tools/services/font_service.py
+++ b/tools/services/font_service.py
@@ -111,7 +111,7 @@ def _create_builder(self, width_mode: WidthMode, language_flavor: LanguageFlavor
         builder.font_metric.horizontal_layout.ascent = layout_param.ascent
         builder.font_metric.horizontal_layout.descent = layout_param.descent
         builder.font_metric.vertical_layout.ascent = math.ceil(layout_param.line_height / 2)
-        builder.font_metric.vertical_layout.descent = math.floor(layout_param.line_height / 2)
+        builder.font_metric.vertical_layout.descent = -math.floor(layout_param.line_height / 2)
         builder.font_metric.x_height = layout_param.x_height
         builder.font_metric.cap_height = layout_param.cap_height