diff --git a/backend/cmd/server/wire_gen.go b/backend/cmd/server/wire_gen.go
index ec8b9dec..60bb17d5 100644
--- a/backend/cmd/server/wire_gen.go
+++ b/backend/cmd/server/wire_gen.go
@@ -229,8 +229,7 @@ func initializeApplication(buildInfo handler.BuildInfo) (*Application, error) {
 	tokenRefreshService := service.ProvideTokenRefreshService(accountRepository, soraAccountRepository, oAuthService, openAIOAuthService, geminiOAuthService, antigravityOAuthService, compositeTokenCacheInvalidator, schedulerCache, configConfig, tempUnschedCache)
 	accountExpiryService := service.ProvideAccountExpiryService(accountRepository)
 	subscriptionExpiryService := service.ProvideSubscriptionExpiryService(userSubscriptionRepository)
-	leaderLocker := repository.NewLeaderLocker(db, redisClient)
-	scheduledTestRunnerService := service.ProvideScheduledTestRunnerService(scheduledTestPlanRepository, scheduledTestService, accountTestService, leaderLocker, configConfig)
+	scheduledTestRunnerService := service.ProvideScheduledTestRunnerService(scheduledTestPlanRepository, scheduledTestService, accountTestService, configConfig)
 	v := provideCleanup(client, redisClient, opsMetricsCollector, opsAggregationService, opsAlertEvaluatorService, opsCleanupService, opsScheduledReportService, opsSystemLogSink, soraMediaCleanupService, schedulerSnapshotService, tokenRefreshService, accountExpiryService, subscriptionExpiryService, usageCleanupService, idempotencyCleanupService, pricingService, emailQueueService, billingCacheService, usageRecordWorkerPool, subscriptionService, oAuthService, openAIOAuthService, geminiOAuthService, antigravityOAuthService, openAIGatewayService, scheduledTestRunnerService)
 	application := &Application{
 		Server:  httpServer,
diff --git a/backend/internal/repository/scheduled_test_repo.go b/backend/internal/repository/scheduled_test_repo.go
index 618edee2..60627702 100644
--- a/backend/internal/repository/scheduled_test_repo.go
+++ b/backend/internal/repository/scheduled_test_repo.go
@@ -3,14 +3,9 @@ package repository
 import (
 	"context"
 	"database/sql"
-	"hash/fnv"
-	"sync"
 	"time"
 
-	"github.com/Wei-Shaw/sub2api/internal/pkg/logger"
 	"github.com/Wei-Shaw/sub2api/internal/service"
-	"github.com/google/uuid"
-	"github.com/redis/go-redis/v9"
 )
 
 // --- Plan Repository ---
@@ -186,83 +181,3 @@ func scanPlans(rows *sql.Rows) ([]*service.ScheduledTestPlan, error) {
 	}
 	return plans, rows.Err()
 }
-
-// --- LeaderLocker ---
-
-var redisReleaseScript = redis.NewScript(`
-if redis.call("GET", KEYS[1]) == ARGV[1] then
-  return redis.call("DEL", KEYS[1])
-end
-return 0
-`)
-
-type leaderLocker struct {
-	db              *sql.DB
-	redisClient     *redis.Client
-	instanceID      string
-	warnNoRedisOnce sync.Once
-}
-
-// NewLeaderLocker creates a LeaderLocker that tries Redis first, then falls back to pg advisory lock.
-func NewLeaderLocker(db *sql.DB, redisClient *redis.Client) service.LeaderLocker {
-	return &leaderLocker{
-		db:          db,
-		redisClient: redisClient,
-		instanceID:  uuid.NewString(),
-	}
-}
-
-func (l *leaderLocker) TryAcquire(ctx context.Context, key string, ttl time.Duration) (func(), bool) {
-	if l.redisClient != nil {
-		ok, err := l.redisClient.SetNX(ctx, key, l.instanceID, ttl).Result()
-		if err == nil {
-			if !ok {
-				return nil, false
-			}
-			return func() {
-				_, _ = redisReleaseScript.Run(ctx, l.redisClient, []string{key}, l.instanceID).Result()
-			}, true
-		}
-		l.warnNoRedisOnce.Do(func() {
-			logger.LegacyPrintf("repository.leader_locker", "[LeaderLocker] Redis SetNX failed; falling back to DB advisory lock: %v", err)
-		})
-	} else {
-		l.warnNoRedisOnce.Do(func() {
-			logger.LegacyPrintf("repository.leader_locker", "[LeaderLocker] Redis not configured; using DB advisory lock")
-		})
-	}
-
-	// Fallback: pg_try_advisory_lock
-	return tryAdvisoryLock(ctx, l.db, hashLockID(key))
-}
-
-func tryAdvisoryLock(ctx context.Context, db *sql.DB, lockID int64) (func(), bool) {
-	if db == nil {
-		return nil, false
-	}
-	conn, err := db.Conn(ctx)
-	if err != nil {
-		return nil, false
-	}
-	acquired := false
-	if err := conn.QueryRowContext(ctx, "SELECT pg_try_advisory_lock($1)", lockID).Scan(&acquired); err != nil {
-		_ = conn.Close()
-		return nil, false
-	}
-	if !acquired {
-		_ = conn.Close()
-		return nil, false
-	}
-	return func() {
-		unlockCtx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
-		defer cancel()
-		_, _ = conn.ExecContext(unlockCtx, "SELECT pg_advisory_unlock($1)", lockID)
-		_ = conn.Close()
-	}, true
-}
-
-func hashLockID(key string) int64 {
-	h := fnv.New64a()
-	_, _ = h.Write([]byte(key))
-	return int64(h.Sum64())
-}
diff --git a/backend/internal/repository/wire.go b/backend/internal/repository/wire.go
index 382004f3..5fe7a98e 100644
--- a/backend/internal/repository/wire.go
+++ b/backend/internal/repository/wire.go
@@ -56,7 +56,6 @@ var ProviderSet = wire.NewSet(
 	NewSoraAccountRepository,         // Sora 账号扩展表仓储
 	NewScheduledTestPlanRepository,   // 定时测试计划仓储
 	NewScheduledTestResultRepository, // 定时测试结果仓储
-	NewLeaderLocker,                  // 分布式 leader 选举
 	NewProxyRepository,
 	NewRedeemCodeRepository,
 	NewPromoCodeRepository,
diff --git a/backend/internal/service/scheduled_test_port.go b/backend/internal/service/scheduled_test_port.go
index 4da33e6d..f795ba00 100644
--- a/backend/internal/service/scheduled_test_port.go
+++ b/backend/internal/service/scheduled_test_port.go
@@ -59,10 +59,3 @@ type ScheduledTestResultRepository interface {
 	ListByPlanID(ctx context.Context, planID int64, limit int) ([]*ScheduledTestResult, error)
 	PruneOldResults(ctx context.Context, planID int64, keepCount int) error
 }
-
-// LeaderLocker provides distributed leader election for background runners.
-// TryAcquire attempts to acquire a named lock and returns a release function
-// and true if successful, or nil and false if the lock is held by another instance.
-type LeaderLocker interface {
-	TryAcquire(ctx context.Context, key string, ttl time.Duration) (release func(), ok bool)
-}
diff --git a/backend/internal/service/scheduled_test_runner_service.go b/backend/internal/service/scheduled_test_runner_service.go
index 1c61c072..45d85624 100644
--- a/backend/internal/service/scheduled_test_runner_service.go
+++ b/backend/internal/service/scheduled_test_runner_service.go
@@ -10,18 +10,13 @@ import (
 	"github.com/robfig/cron/v3"
 )
 
-const (
-	scheduledTestLeaderLockKey     = "scheduled_test:runner:leader"
-	scheduledTestLeaderLockTTL     = 2 * time.Minute
-	scheduledTestDefaultMaxWorkers = 10
-)
+const scheduledTestDefaultMaxWorkers = 10
 
 // ScheduledTestRunnerService periodically scans due test plans and executes them.
 type ScheduledTestRunnerService struct {
 	planRepo       ScheduledTestPlanRepository
 	scheduledSvc   *ScheduledTestService
 	accountTestSvc *AccountTestService
-	locker         LeaderLocker
 	cfg            *config.Config
 
 	cron      *cron.Cron
@@ -34,14 +29,12 @@ func NewScheduledTestRunnerService(
 	planRepo ScheduledTestPlanRepository,
 	scheduledSvc *ScheduledTestService,
 	accountTestSvc *AccountTestService,
-	locker LeaderLocker,
 	cfg *config.Config,
 ) *ScheduledTestRunnerService {
 	return &ScheduledTestRunnerService{
 		planRepo:       planRepo,
 		scheduledSvc:   scheduledSvc,
 		accountTestSvc: accountTestSvc,
-		locker:         locker,
 		cfg:            cfg,
 	}
 }
@@ -95,17 +88,6 @@ func (s *ScheduledTestRunnerService) runScheduled() {
 	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Minute)
 	defer cancel()
 
-	// Skip leader election in simple mode.
-	if s.cfg == nil || s.cfg.RunMode != config.RunModeSimple {
-		release, ok := s.locker.TryAcquire(ctx, scheduledTestLeaderLockKey, scheduledTestLeaderLockTTL)
-		if !ok {
-			return
-		}
-		if release != nil {
-			defer release()
-		}
-	}
-
 	now := time.Now()
 	plans, err := s.planRepo.ListDue(ctx, now)
 	if err != nil {
@@ -118,8 +100,7 @@ func (s *ScheduledTestRunnerService) runScheduled() {
 
 	logger.LegacyPrintf("service.scheduled_test_runner", "[ScheduledTestRunner] found %d due plans", len(plans))
 
-	maxWorkers := scheduledTestDefaultMaxWorkers
-	sem := make(chan struct{}, maxWorkers)
+	sem := make(chan struct{}, scheduledTestDefaultMaxWorkers)
 	var wg sync.WaitGroup
 
 	for _, plan := range plans {
@@ -146,7 +127,6 @@ func (s *ScheduledTestRunnerService) runOnePlan(ctx context.Context, plan *Sched
 		logger.LegacyPrintf("service.scheduled_test_runner", "[ScheduledTestRunner] plan=%d SaveResult error: %v", plan.ID, err)
 	}
 
-	// Compute next run
 	nextRun, err := computeNextRun(plan.CronExpression, time.Now())
 	if err != nil {
 		logger.LegacyPrintf("service.scheduled_test_runner", "[ScheduledTestRunner] plan=%d computeNextRun error: %v", plan.ID, err)
diff --git a/backend/internal/service/wire.go b/backend/internal/service/wire.go
index e50145b4..42fbadf6 100644
--- a/backend/internal/service/wire.go
+++ b/backend/internal/service/wire.go
@@ -287,10 +287,9 @@ func ProvideScheduledTestRunnerService(
 	planRepo ScheduledTestPlanRepository,
 	scheduledSvc *ScheduledTestService,
 	accountTestSvc *AccountTestService,
-	locker LeaderLocker,
 	cfg *config.Config,
 ) *ScheduledTestRunnerService {
-	svc := NewScheduledTestRunnerService(planRepo, scheduledSvc, accountTestSvc, locker, cfg)
+	svc := NewScheduledTestRunnerService(planRepo, scheduledSvc, accountTestSvc, cfg)
 	svc.Start()
 	return svc
 }