diff --git a/src/hooks/usePolygon.js b/src/hooks/usePolygon.js
index 99845d46..1dc3f231 100644
--- a/src/hooks/usePolygon.js
+++ b/src/hooks/usePolygon.js
@@ -7,7 +7,7 @@ import { isSamePoint, removeDuplicatePolygons } from '@/util/qpolygon-utils'
 import { flowDisplaySelector } from '@/store/settingAtom'
 import { fontSelector } from '@/store/fontAtom'
 import { QLine } from '@/components/fabric/QLine'
-import { POLYGON_TYPE } from '@/common/common'
+import { LINE_TYPE, POLYGON_TYPE } from '@/common/common'
 
 export const usePolygon = () => {
   const canvas = useRecoilValue(canvasState)
@@ -909,6 +909,29 @@ export const usePolygon = () => {
 
     const allLines = [...polygonLines, ...innerLines]
 
+    // 2025-02-19 대각선은 케라바, 직선은 용마루로 세팅
+    innerLines.forEach((innerLine) => {
+      const startPoint = innerLine.startPoint
+      const endPoint = innerLine.endPoint
+
+      // startPoint와 endPoint의 각도가 0,90,180,270이면 직선으로 판단
+      if (Math.abs(startPoint.x - endPoint.x) < 2 || Math.abs(startPoint.y - endPoint.y) < 2) {
+        if (!innerLine.attributes || !innerLine.attributes.type) {
+          innerLine.attributes = {
+            ...innerLine.attributes,
+            type: LINE_TYPE.SUBLINE.RIDGE,
+          }
+        }
+      } else {
+        if (!innerLine.attributes || !innerLine.attributes.type) {
+          innerLine.attributes = {
+            ...innerLine.attributes,
+            type: LINE_TYPE.SUBLINE.GABLE,
+          }
+        }
+      }
+    })
+
     /**
      * 왼쪽 상단을 startPoint로 전부 변경
      */