diff --git a/android/app/build.gradle b/android/app/build.gradle
index 873ec71..c128b69 100644
--- a/android/app/build.gradle
+++ b/android/app/build.gradle
@@ -7,8 +7,8 @@ android {
         applicationId "com.tasktrees.app"
         minSdkVersion rootProject.ext.minSdkVersion
         targetSdkVersion rootProject.ext.targetSdkVersion
-        versionCode 7
-        versionName "1.2.2"
+        versionCode 8
+        versionName "1.2.3"
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
         aaptOptions {
              // Files and dirs to omit from the packaged assets dir, modified to accommodate modern web apps.
diff --git a/package-lock.json b/package-lock.json
index 8dda8fb..3d8abd3 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "tasktree-s",
-  "version": "1.2.2",
+  "version": "1.2.3",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "tasktree-s",
-      "version": "1.2.2",
+      "version": "1.2.3",
       "dependencies": {
         "@capacitor-firebase/authentication": "^5.4.1",
         "@capacitor/android": "^5.7.4",
diff --git a/package.json b/package.json
index 082cc02..9f75a7c 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "tasktree-s",
   "private": true,
-  "version": "1.2.2",
+  "version": "1.2.3",
   "type": "module",
   "scripts": {
     "dev": "vite",
diff --git a/src/components/SortableTree/SortableTree.tsx b/src/components/SortableTree/SortableTree.tsx
index 6b88799..0f0b5b5 100644
--- a/src/components/SortableTree/SortableTree.tsx
+++ b/src/components/SortableTree/SortableTree.tsx
@@ -372,9 +372,11 @@ export function SortableTree({ collapsible, indicator = false, indentationWidth
         setItems(newItems);
       }
     } else {
-      // 新規タスクの場合、新規タスクを削除
+      // 新規タスクの場合、新規タスクを先頭に移動し、IDを最大ID+1に更新
       if (active.id === activeNewTaskId || active.id === activeQuickMemoId) {
-        setItems(items.filter((item) => item.id !== active.id));
+        const newId = (findMaxId(items) + 1).toString();
+        const updatedItems = items.map((item) => (item.id === active.id ? { ...item, id: newId, value: '' } : item));
+        setItems([updatedItems.find((item) => item.id === newId)!, ...items.filter((item) => item.id !== active.id)]);
         const newActiveId = (parseInt(active.id.toString()) - 1).toString();
         if (active.id === activeNewTaskId) {
           setActiveNewTaskId(newActiveId);
@@ -387,9 +389,11 @@ export function SortableTree({ collapsible, indicator = false, indentationWidth
 
   function handleDragCancel() {
     resetState();
-    // 新規タスクの場合、新規タスクを削除
+    // 新規タスクの場合、新規タスクを先頭に移動し、IDを最大ID+1に更新
     if (activeId === activeNewTaskId || activeId === activeQuickMemoId) {
-      setItems(items.filter((item) => item.id !== activeId));
+      const newId = (findMaxId(items) + 1).toString();
+      const updatedItems = items.map((item) => (item.id === activeId ? { ...item, id: newId, value: '' } : item));
+      setItems([updatedItems.find((item) => item.id === newId)!, ...items.filter((item) => item.id !== activeId)]);
       const newActiveId = (parseInt(activeId.toString()) - 1).toString();
       if (activeId === activeNewTaskId) {
         setActiveNewTaskId(newActiveId);