diff --git a/src/hooks/usePolygon.js b/src/hooks/usePolygon.js
index f72b6446..988213f7 100644
--- a/src/hooks/usePolygon.js
+++ b/src/hooks/usePolygon.js
@@ -765,6 +765,14 @@ export const usePolygon = () => {
   const splitPolygonWithLines = (polygon) => {
     polygon.set({ visible: false })
 
+    const auxiliaryLines = canvas
+      .getObjects()
+      .filter((obj) => obj.name === 'auxiliaryLine' && polygon.inPolygonImproved(obj.startPoint) && polygon.inPolygonImproved(obj.endPoint))
+
+    auxiliaryLines.forEach((auxiliaryLine) => {
+      polygon.innerLines.push(auxiliaryLine)
+    })
+
     let innerLines = [...polygon.innerLines].filter((line) => line.visible)
 
     /*// innerLine이 세팅이 안되어있는경우 찾아서 세팅한다.
@@ -1263,7 +1271,6 @@ export const usePolygon = () => {
     })
 
     //지붕 완료 후 보조선을 전부 제거한다.
-    const auxiliaryLines = canvas.getObjects().filter((obj) => obj.name === 'auxiliaryLine')
 
     auxiliaryLines.forEach((line) => {
       canvas.remove(line)