diff --git a/app/Plugins/User/Searchs/SearchsPlugin.php b/app/Plugins/User/Searchs/SearchsPlugin.php
index f4b2ae56f..a168a3960 100644
--- a/app/Plugins/User/Searchs/SearchsPlugin.php
+++ b/app/Plugins/User/Searchs/SearchsPlugin.php
@@ -420,6 +420,11 @@ public function saveBuckets($request, $page_id, $frame_id, $id = null)
             $message = '設定を変更しました。';
         }
 
+        $target_frame_ids = $request->target_frame_ids;
+        if (intval($request->frame_select) == SearchsFrameSelect::all_frames && !$request->has('target_frame_ids')) {
+            $target_frame_ids = empty($searchs->target_frame_ids) ? [] : explode(',', $searchs->target_frame_ids);
+        }
+
         // 設定データ
         $searchs->search_name       = $request->search_name;
         $searchs->count             = $request->count;
@@ -427,7 +432,7 @@ public function saveBuckets($request, $page_id, $frame_id, $id = null)
         $searchs->view_posted_at    = intval($request->view_posted_at);
         $searchs->target_plugins    = implode(',', $request->target_plugin);
         $searchs->frame_select      = intval($request->frame_select);
-        $searchs->target_frame_ids  = empty($request->target_frame_ids) ? "": implode(',', $request->target_frame_ids);
+        $searchs->target_frame_ids  = empty($target_frame_ids) ? "": implode(',', $target_frame_ids);
         $searchs->recieve_keyword   = intval($request->recieve_keyword);
         $searchs->page_select       = intval($request->page_select);
 
diff --git a/resources/views/plugins/user/searchs/default/searchs_edit_search.blade.php b/resources/views/plugins/user/searchs/default/searchs_edit_search.blade.php
index 245001bb4..d92d7cf48 100644
--- a/resources/views/plugins/user/searchs/default/searchs_edit_search.blade.php
+++ b/resources/views/plugins/user/searchs/default/searchs_edit_search.blade.php
@@ -46,7 +46,7 @@
 @if (isset($searchs))
     @if (!$searchs->id && !$create_flag)
     @else
-        <form action="{{url('/')}}/plugin/searchs/saveBuckets/{{$page->id}}/{{$frame_id}}#frame-{{$frame->id}}" method="POST" class="">
+        <form action="{{url('/')}}/plugin/searchs/saveBuckets/{{$page->id}}/{{$frame_id}}#frame-{{$frame->id}}" method="POST" class="" id="searchs_edit_form_{{$frame->id}}">
             {{ csrf_field() }}
 
             {{-- create_flag がtrue の場合、新規作成するためにsearchs_id を空にする --}}
@@ -167,15 +167,42 @@
                 </div>
             </div>
 
+            @php
+                $selected_frame_select = old('frame_select', $searchs->frame_select);
+            @endphp
+
             <div class="form-group row mb-0">
                 <label class="{{$frame->getSettingLabelClass()}}">フレームの選択</label>
                 <div class="{{$frame->getSettingInputClass(true)}}">
                     @foreach (SearchsFrameSelect::enum as $key => $item)
                         <div class="custom-control custom-radio custom-control-inline">
-                            @if(old('frame_select', $searchs->frame_select) == $key)
-                                <input type="radio" value="{{$key}}" id="frame_select_{{$key}}" name="frame_select" class="custom-control-input" checked="checked">
+                            @if($selected_frame_select == $key)
+                                <input
+                                    type="radio"
+                                    value="{{$key}}"
+                                    id="frame_select_{{$key}}"
+                                    name="frame_select"
+                                    class="custom-control-input"
+                                    checked="checked"
+                                    @if($key == SearchsFrameSelect::all_frames)
+                                        data-toggle="collapse" data-target="#collapse_frame_select{{$frame_id}}.show"
+                                    @else
+                                        data-toggle="collapse" data-target="#collapse_frame_select{{$frame_id}}:not(.show)" aria-expanded="true" aria-controls="collapse_frame_select{{$frame_id}}"
+                                    @endif
+                                >
                             @else
-                                <input type="radio" value="{{$key}}" id="frame_select_{{$key}}" name="frame_select" class="custom-control-input">
+                                <input
+                                    type="radio"
+                                    value="{{$key}}"
+                                    id="frame_select_{{$key}}"
+                                    name="frame_select"
+                                    class="custom-control-input"
+                                    @if($key == SearchsFrameSelect::all_frames)
+                                        data-toggle="collapse" data-target="#collapse_frame_select{{$frame_id}}.show"
+                                    @else
+                                        data-toggle="collapse" data-target="#collapse_frame_select{{$frame_id}}:not(.show)" aria-expanded="true" aria-controls="collapse_frame_select{{$frame_id}}"
+                                    @endif
+                                >
                             @endif
                             <label class="custom-control-label" for="frame_select_{{$key}}">{{ SearchsFrameSelect::getDescription($key) }}</label>
                         </div>
@@ -193,9 +220,9 @@
                 </div>
             </div>
 
-            <div class="form-group row">
+            <div class="form-group row collapse" id="collapse_frame_select{{$frame_id}}">
                 <label class="{{$frame->getSettingLabelClass()}}">対象ページ - フレーム</label>
-                <div class="{{$frame->getSettingInputClass(false, true)}}">
+                <div class="{{$frame->getSettingInputClass(false, true)}}" id="searchs_target_frames_{{$frame->id}}">
                     <ul class="nav nav-pills" role="tablist">
                         @foreach(SearchsTargetPlugin::getPluginsCanSpecifiedFrames() as $target_plugin => $target_plugin_full)
                             <li class="nav-item">
@@ -275,4 +302,35 @@
         @endif
     @endif
 @endif
+
+<script>
+    (function() {
+        const allFramesValue = '{{ SearchsFrameSelect::all_frames }}';
+        const targetFramesArea = document.getElementById('searchs_target_frames_{{ $frame->id }}');
+        const collapseTargetFrames = document.getElementById('collapse_frame_select{{ $frame_id }}');
+        const searchsEditForm = document.getElementById('searchs_edit_form_{{ $frame->id }}');
+        const frameSelects = searchsEditForm ? searchsEditForm.querySelectorAll('input[name="frame_select"]') : [];
+
+        if (!searchsEditForm || !collapseTargetFrames || !targetFramesArea || frameSelects.length === 0) {
+            return;
+        }
+
+        const setTargetFramesDisabled = function() {
+            const checkedFrameSelect = searchsEditForm.querySelector('input[name="frame_select"]:checked');
+            const disabled = checkedFrameSelect && checkedFrameSelect.value === allFramesValue;
+
+            targetFramesArea.setAttribute('aria-disabled', disabled ? 'true' : 'false');
+        };
+
+        frameSelects.forEach(function(frameSelect) {
+            frameSelect.addEventListener('change', setTargetFramesDisabled);
+        });
+
+        setTargetFramesDisabled();
+
+        @if (isset($selected_frame_select) && $selected_frame_select == SearchsFrameSelect::selected_only)
+            $('#collapse_frame_select{{$frame_id}}').collapse('show')
+        @endif
+    })();
+</script>
 @endsection
diff --git a/tests/Feature/Plugins/User/Searchs/SearchsTargetFrameSaveFeatureTest.php b/tests/Feature/Plugins/User/Searchs/SearchsTargetFrameSaveFeatureTest.php
new file mode 100644
index 000000000..cf2f99acd
--- /dev/null
+++ b/tests/Feature/Plugins/User/Searchs/SearchsTargetFrameSaveFeatureTest.php
@@ -0,0 +1,125 @@
+<?php
+
+namespace Tests\Feature\Plugins\User\Searchs;
+
+use App\Enums\SearchsFrameSelect;
+use App\Enums\SearchsPageSelect;
+use App\Models\Common\Buckets;
+use App\Models\User\Searchs\Searchs;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Tests\Feature\Plugins\User\DefaultBucketRolesFeatureTestTrait;
+use Tests\TestCase;
+
+/**
+ * サイト内検索設定の対象フレーム保存を検証する。
+ *
+ * 設定保存の公開ルートを通して、フレーム選択UIの表示状態に左右されず、
+ * 既存の対象フレーム指定が意図せず失われないことを守る。
+ */
+class SearchsTargetFrameSaveFeatureTest extends TestCase
+{
+    use DefaultBucketRolesFeatureTestTrait;
+    use RefreshDatabase;
+
+    /**
+     * テスト前に初期データを投入する。
+     */
+    protected function setUp(): void
+    {
+        parent::setUp();
+
+        $this->seed();
+    }
+
+    /**
+     * 「全て表示する」で保存しても、画面上では使わない既存の対象フレーム指定を保持すること。
+     */
+    public function testSaveBucketsKeepsTargetFrameIdsWhenAllFramesRequestOmitsThem(): void
+    {
+        $admin = $this->createContentAdminUser();
+        [$page, $frame] = $this->createPluginFrame('searchs');
+        $searchs = $this->createSearchsBucket($frame->id, '10,20');
+
+        $response = $this->actingAs($admin)->post("/redirect/plugin/searchs/saveBuckets/{$page->id}/{$frame->id}", [
+            'redirect_path' => url("/plugin/searchs/editBuckets/{$page->id}/{$frame->id}#frame-{$frame->id}"),
+            'searchs_id' => $searchs->id,
+            'search_name' => 'サイト内検索を更新',
+            'count' => 20,
+            'view_posted_name' => 0,
+            'view_posted_at' => 0,
+            'target_plugin' => ['blogs' => 'blogs'],
+            'frame_select' => SearchsFrameSelect::all_frames,
+            'recieve_keyword' => 0,
+            'page_select' => SearchsPageSelect::all_pages,
+        ]);
+
+        $response->assertStatus(302);
+        $this->assertDatabaseHas('searchs', [
+            'id' => $searchs->id,
+            'frame_select' => SearchsFrameSelect::all_frames,
+            'target_frame_ids' => '10,20',
+        ]);
+    }
+
+    /**
+     * 「選択したものだけ表示する」で保存した場合は、送信された対象フレーム指定へ更新すること。
+     */
+    public function testSaveBucketsUpdatesTargetFrameIdsWhenSelectedOnlySendsThem(): void
+    {
+        $admin = $this->createContentAdminUser();
+        [$page, $frame] = $this->createPluginFrame('searchs');
+        $searchs = $this->createSearchsBucket($frame->id, '10,20');
+
+        $response = $this->actingAs($admin)->post("/redirect/plugin/searchs/saveBuckets/{$page->id}/{$frame->id}", [
+            'redirect_path' => url("/plugin/searchs/editBuckets/{$page->id}/{$frame->id}#frame-{$frame->id}"),
+            'searchs_id' => $searchs->id,
+            'search_name' => 'サイト内検索を更新',
+            'count' => 20,
+            'view_posted_name' => 0,
+            'view_posted_at' => 0,
+            'target_plugin' => ['blogs' => 'blogs'],
+            'frame_select' => SearchsFrameSelect::selected_only,
+            'target_frame_ids' => [30 => 30],
+            'recieve_keyword' => 0,
+            'page_select' => SearchsPageSelect::all_pages,
+        ]);
+
+        $response->assertStatus(302);
+        $this->assertDatabaseHas('searchs', [
+            'id' => $searchs->id,
+            'frame_select' => SearchsFrameSelect::selected_only,
+            'target_frame_ids' => '30',
+        ]);
+    }
+
+    /**
+     * 既存バケツとサイト内検索設定を作成し、指定フレームに紐づける。
+     */
+    private function createSearchsBucket(int $frame_id, string $target_frame_ids): Searchs
+    {
+        $bucket = Buckets::factory()->create([
+            'bucket_name' => 'サイト内検索',
+            'plugin_name' => 'searchs',
+        ]);
+        $this->assertDatabaseHas('frames', [
+            'id' => $frame_id,
+        ]);
+
+        app('db')->table('frames')
+            ->where('id', $frame_id)
+            ->update(['bucket_id' => $bucket->id]);
+
+        return Searchs::create([
+            'bucket_id' => $bucket->id,
+            'search_name' => 'サイト内検索',
+            'count' => 10,
+            'view_posted_name' => 0,
+            'view_posted_at' => 0,
+            'target_plugins' => 'blogs',
+            'frame_select' => SearchsFrameSelect::selected_only,
+            'target_frame_ids' => $target_frame_ids,
+            'recieve_keyword' => 0,
+            'page_select' => SearchsPageSelect::all_pages,
+        ]);
+    }
+}