diff --git a/resources/views/rd/planning-design/index.blade.php b/resources/views/rd/planning-design/index.blade.php
index 1bf71073..81d7d037 100644
--- a/resources/views/rd/planning-design/index.blade.php
+++ b/resources/views/rd/planning-design/index.blade.php
@@ -3278,21 +3278,24 @@ function planningCanvas() {
         },
 
         sbUndo() {
-            if (this._sbHistoryIdx <= 0) return;
+            if (this._sbHistory.length === 0) return;
             const page = this.sbCurrentPage;
             if (!page) return;
-            // 처음 undo 시 현재 상태 저장
+            // 처음 undo 시 현재(변경 후) 상태를 히스토리 끝에 저장
+            const curSnap = JSON.parse(JSON.stringify(page.blocks || []));
             if (this._sbHistoryIdx === this._sbHistory.length - 1) {
-                const snap = JSON.parse(JSON.stringify(page.blocks || []));
-                if (this._sbHistory.length === 0 || JSON.stringify(this._sbHistory[this._sbHistoryIdx]) !== JSON.stringify(snap)) {
-                    this._sbHistory.push(snap);
+                const lastSnap = JSON.stringify(this._sbHistory[this._sbHistoryIdx]);
+                if (lastSnap !== JSON.stringify(curSnap)) {
+                    this._sbHistory.push(curSnap);
                     this._sbHistoryIdx = this._sbHistory.length - 1;
                 }
             }
+            if (this._sbHistoryIdx <= 0) return;
             this._sbHistoryIdx--;
             this._sbHistoryPaused = true;
             page.blocks = JSON.parse(JSON.stringify(this._sbHistory[this._sbHistoryIdx]));
             this.sbSelectedBlock = null;
+            this.sbMultiSelected = [];
             this._sbHistoryPaused = false;
             this.autoSave();
         },
@@ -3304,6 +3307,7 @@ function planningCanvas() {
             this._sbHistoryIdx++;
             this._sbHistoryPaused = true;
             page.blocks = JSON.parse(JSON.stringify(this._sbHistory[this._sbHistoryIdx]));
+            this.sbMultiSelected = [];
             this.sbSelectedBlock = null;
             this._sbHistoryPaused = false;
             this.autoSave();