diff --git a/database/migrations/2026_05_22_140000_add_frontend_play_rules_html_i18n_settings.php b/database/migrations/2026_05_22_140000_add_frontend_play_rules_html_i18n_settings.php
new file mode 100644
index 0000000..f5df7fa
--- /dev/null
+++ b/database/migrations/2026_05_22_140000_add_frontend_play_rules_html_i18n_settings.php
@@ -0,0 +1,50 @@
+<?php
+
+use App\Models\LotterySetting;
+use Illuminate\Database\Migrations\Migration;
+
+/**
+ * 玩法规则 HTML：由单键 frontend.play_rules_html 拆分为 zh/en/ne 三语键。
+ * 已有内容迁移到 frontend.play_rules_html_zh。
+ */
+return new class extends Migration
+{
+    private const LEGACY_KEY = 'frontend.play_rules_html';
+
+    private const I18N_KEYS = [
+        'frontend.play_rules_html_zh' => '玩家端玩法规则页 HTML（中文）',
+        'frontend.play_rules_html_en' => '玩家端玩法规则页 HTML（English）',
+        'frontend.play_rules_html_ne' => '玩家端玩法规则页 HTML（नेपाली）',
+    ];
+
+    public function up(): void
+    {
+        $legacyRow = LotterySetting::query()->where('setting_key', self::LEGACY_KEY)->first();
+        $legacyValue = $legacyRow?->value_json;
+
+        foreach (self::I18N_KEYS as $key => $description) {
+            if (LotterySetting::query()->where('setting_key', $key)->exists()) {
+                continue;
+            }
+
+            $value = '';
+            if ($key === 'frontend.play_rules_html_zh' && is_string($legacyValue) && trim($legacyValue) !== '') {
+                $value = $legacyValue;
+            }
+
+            LotterySetting::query()->create([
+                'setting_key' => $key,
+                'value_json' => $value,
+                'group_name' => 'frontend',
+                'description_zh' => $description,
+            ]);
+        }
+    }
+
+    public function down(): void
+    {
+        LotterySetting::query()
+            ->whereIn('setting_key', array_keys(self::I18N_KEYS))
+            ->delete();
+    }
+};
diff --git a/database/seeders/LotterySettingsSeeder.php b/database/seeders/LotterySettingsSeeder.php
index fc67309..509ab5d 100644
--- a/database/seeders/LotterySettingsSeeder.php
+++ b/database/seeders/LotterySettingsSeeder.php
@@ -93,7 +93,28 @@ final class LotterySettingsSeeder extends Seeder
             'frontend.play_rules_html',
             '',
             'frontend',
-            '玩家端玩法规则页面显示的自定义 HTML 富文本内容',
+            '玩家端玩法规则页面显示的自定义 HTML（遗留键，保存时与中文键同步）',
+        );
+
+        LotterySettings::put(
+            'frontend.play_rules_html_zh',
+            '',
+            'frontend',
+            '玩家端玩法规则页 HTML（中文）',
+        );
+
+        LotterySettings::put(
+            'frontend.play_rules_html_en',
+            '',
+            'frontend',
+            '玩家端玩法规则页 HTML（English）',
+        );
+
+        LotterySettings::put(
+            'frontend.play_rules_html_ne',
+            '',
+            'frontend',
+            '玩家端玩法规则页 HTML（नेपाली）',
         );
     }
 }