diff --git a/database/migrations/2026_02_28_100000_add_sub_manager_to_equipments_table.php b/database/migrations/2026_02_28_100000_add_sub_manager_to_equipments_table.php
new file mode 100644
index 0000000..c1c195f
--- /dev/null
+++ b/database/migrations/2026_02_28_100000_add_sub_manager_to_equipments_table.php
@@ -0,0 +1,23 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        Schema::table('equipments', function (Blueprint $table) {
+            $table->foreignId('sub_manager_id')->nullable()->after('manager_id')
+                ->comment('부 담당자 ID (users.id)');
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::table('equipments', function (Blueprint $table) {
+            $table->dropColumn('sub_manager_id');
+        });
+    }
+};
diff --git a/database/migrations/2026_02_28_100100_add_inspection_cycle_to_templates_table.php b/database/migrations/2026_02_28_100100_add_inspection_cycle_to_templates_table.php
new file mode 100644
index 0000000..5750d5f
--- /dev/null
+++ b/database/migrations/2026_02_28_100100_add_inspection_cycle_to_templates_table.php
@@ -0,0 +1,67 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\DB;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        // 컬럼 추가 (이미 존재하면 건너뜀)
+        if (! Schema::hasColumn('equipment_inspection_templates', 'inspection_cycle')) {
+            Schema::table('equipment_inspection_templates', function (Blueprint $table) {
+                $table->string('inspection_cycle', 20)->default('daily')->after('equipment_id')
+                    ->comment('점검주기: daily/weekly/monthly/bimonthly/quarterly/semiannual');
+            });
+        }
+
+        // FK 삭제 → 유니크 변경 → FK 재생성 (개별 statement)
+        $this->dropFkIfExists('equipment_inspection_templates', 'equipment_inspection_templates_equipment_id_foreign');
+        $this->dropUniqueIfExists('equipment_inspection_templates', 'uq_equipment_item_no');
+
+        Schema::table('equipment_inspection_templates', function (Blueprint $table) {
+            $table->unique(['equipment_id', 'inspection_cycle', 'item_no'], 'uq_equipment_cycle_item_no');
+            $table->index('inspection_cycle', 'idx_insp_tmpl_cycle');
+
+            $table->foreign('equipment_id')
+                ->references('id')
+                ->on('equipments')
+                ->onDelete('cascade');
+        });
+    }
+
+    public function down(): void
+    {
+        $this->dropFkIfExists('equipment_inspection_templates', 'equipment_inspection_templates_equipment_id_foreign');
+
+        Schema::table('equipment_inspection_templates', function (Blueprint $table) {
+            $table->dropIndex('idx_insp_tmpl_cycle');
+            $table->dropUnique('uq_equipment_cycle_item_no');
+            $table->unique(['equipment_id', 'item_no'], 'uq_equipment_item_no');
+            $table->dropColumn('inspection_cycle');
+
+            $table->foreign('equipment_id')
+                ->references('id')
+                ->on('equipments')
+                ->onDelete('cascade');
+        });
+    }
+
+    private function dropFkIfExists(string $table, string $fkName): void
+    {
+        $fks = DB::select("SELECT CONSTRAINT_NAME FROM information_schema.TABLE_CONSTRAINTS WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = ? AND CONSTRAINT_TYPE = 'FOREIGN KEY' AND CONSTRAINT_NAME = ?", [$table, $fkName]);
+        if (count($fks) > 0) {
+            DB::statement("ALTER TABLE `{$table}` DROP FOREIGN KEY `{$fkName}`");
+        }
+    }
+
+    private function dropUniqueIfExists(string $table, string $indexName): void
+    {
+        $indexes = DB::select("SHOW INDEX FROM `{$table}` WHERE Key_name = ?", [$indexName]);
+        if (count($indexes) > 0) {
+            DB::statement("ALTER TABLE `{$table}` DROP INDEX `{$indexName}`");
+        }
+    }
+};
diff --git a/database/migrations/2026_02_28_100200_add_inspection_cycle_to_inspections_table.php b/database/migrations/2026_02_28_100200_add_inspection_cycle_to_inspections_table.php
new file mode 100644
index 0000000..0de3fe6
--- /dev/null
+++ b/database/migrations/2026_02_28_100200_add_inspection_cycle_to_inspections_table.php
@@ -0,0 +1,43 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\DB;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        Schema::table('equipment_inspections', function (Blueprint $table) {
+            $table->string('inspection_cycle', 20)->default('daily')->after('equipment_id')
+                ->comment('점검주기: daily/weekly/monthly/bimonthly/quarterly/semiannual');
+        });
+
+        // 기존 레코드를 daily로 설정
+        DB::statement("UPDATE equipment_inspections SET inspection_cycle = 'daily' WHERE inspection_cycle = '' OR inspection_cycle IS NULL");
+
+        Schema::table('equipment_inspections', function (Blueprint $table) {
+            // 기존 유니크/인덱스 삭제
+            $table->dropUnique('uq_inspection_month');
+            $table->dropIndex('idx_inspection_ym');
+
+            // cycle 포함 유니크/인덱스 추가
+            $table->unique(['tenant_id', 'equipment_id', 'inspection_cycle', 'year_month'], 'uq_inspection_cycle_period');
+            $table->index(['tenant_id', 'inspection_cycle', 'year_month'], 'idx_inspection_cycle_period');
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::table('equipment_inspections', function (Blueprint $table) {
+            $table->dropIndex('idx_inspection_cycle_period');
+            $table->dropUnique('uq_inspection_cycle_period');
+
+            $table->unique(['tenant_id', 'equipment_id', 'year_month'], 'uq_inspection_month');
+            $table->index(['tenant_id', 'year_month'], 'idx_inspection_ym');
+
+            $table->dropColumn('inspection_cycle');
+        });
+    }
+};