diff --git a/internal/repository/refresh_token_repository.go b/internal/repository/refresh_token_repository.go
index b759d97..55d89ed 100644
--- a/internal/repository/refresh_token_repository.go
+++ b/internal/repository/refresh_token_repository.go
@@ -46,16 +46,20 @@ func (r *RefreshTokenRepository) RevokeByUserID(ctx context.Context, userID stri
 	})
 }
 
-// RevokeOldestActiveByUserID keeps at most limit active refresh tokens for a
-// user by revoking the oldest non-expired, non-revoked tokens.
-func (r *RefreshTokenRepository) RevokeOldestActiveByUserID(ctx context.Context, userID string, limit int) error {
+// RevokeOldestActiveLegacyByUserID keeps at most limit active refresh tokens
+// for a user among tokens that are not bound to a device auth session
+// (legacy web clients). Device sessions are independent: trimming one
+// device's token because another device logged in would silently sign the
+// first device out even though its session is still valid.
+func (r *RefreshTokenRepository) RevokeOldestActiveLegacyByUserID(ctx context.Context, userID string, limit int) error {
 	if limit < 1 {
 		limit = 1
 	}
 	return withSQLiteBusyRetry(ctx, func() error {
 		var tokens []model.RefreshToken
 		if err := r.db.WithContext(ctx).
-			Where("user_id = ? AND revoked = ? AND expires_at > ?", userID, false, time.Now()).
+			Where("user_id = ? AND revoked = ? AND expires_at > ? AND (auth_session_id IS NULL OR auth_session_id = '')",
+				userID, false, time.Now()).
 			Order("created_at desc, id desc").
 			Find(&tokens).Error; err != nil {
 			return err
diff --git a/internal/service/auth_session_test.go b/internal/service/auth_session_test.go
index e4b7ee7..fe8584e 100644
--- a/internal/service/auth_session_test.go
+++ b/internal/service/auth_session_test.go
@@ -3,6 +3,7 @@ package service
 import (
 	"context"
 	"errors"
+	"fmt"
 	"testing"
 	"time"
 
@@ -163,6 +164,52 @@ func TestRefreshKeepsSessionAssociation(t *testing.T) {
 	}
 }
 
+// TestMobileDeviceSessionsDoNotTrimEachOther 覆盖同一账号多设备登录：
+// 每台设备有独立认证会话与刷新令牌，新设备登录或任一设备刷新都不应撤销
+// 其他设备的刷新令牌。历史实现把「最大同时登录终端」直接作用在刷新令牌
+// 上，第 N+1 台设备登录会把最早那台设备的刷新令牌标记为已撤销，那台设备
+// 下一次刷新就会收到 SESSION_REVOKED，被强制退回登录页。
+func TestMobileDeviceSessionsDoNotTrimEachOther(t *testing.T) {
+	sessions, tokens, repos := newAuthSessionTestEnv(t)
+	ctx := context.Background()
+	user := seedSessionUser(t, repos)
+
+	// 默认上限是 3，这里故意登录 4 台设备。
+	const devices = 4
+	pairs := make([]*TokenPair, 0, devices)
+	for i := 0; i < devices; i++ {
+		session, err := sessions.Create(ctx, CreateAuthSessionInput{
+			UserID:     user.ID,
+			DeviceID:   fmt.Sprintf("device-%02d", i),
+			DeviceName: fmt.Sprintf("Phone %d", i+1),
+		})
+		if err != nil {
+			t.Fatalf("create session %d: %v", i+1, err)
+		}
+		pair, err := tokens.IssuePairForSession(ctx, user.ID, user.Role, user.Tier, session.ID)
+		if err != nil {
+			t.Fatalf("issue pair %d: %v", i+1, err)
+		}
+		pairs = append(pairs, pair)
+	}
+
+	for i, pair := range pairs {
+		row, err := repos.RefreshToken.FindByHash(ctx, repository.HashToken(pair.RefreshToken))
+		if err != nil {
+			t.Fatalf("load device %d token: %v", i+1, err)
+		}
+		if row == nil {
+			t.Fatalf("device %d refresh token missing", i+1)
+		}
+		if row.Revoked {
+			t.Fatalf("device %d refresh token was revoked by another device", i+1)
+		}
+		if _, err := tokens.Refresh(ctx, pair.RefreshToken); err != nil {
+			t.Fatalf("device %d refresh failed: %v", i+1, err)
+		}
+	}
+}
+
 func TestServerIdentityPersistsAcrossInstances(t *testing.T) {
 	db := newServiceTestDB(t, &model.Setting{})
 	repos := repository.New(db)
diff --git a/internal/service/token_svc.go b/internal/service/token_svc.go
index b887765..36ab925 100644
--- a/internal/service/token_svc.go
+++ b/internal/service/token_svc.go
@@ -170,8 +170,16 @@ func (s *TokenService) storeRefreshToken(ctx context.Context, rt *model.RefreshT
 	if err := s.repo.RefreshToken.Create(ctx, rt); err != nil {
 		return err
 	}
-	if err := s.repo.RefreshToken.RevokeOldestActiveByUserID(ctx, rt.UserID, s.maxActiveRefreshTokens(ctx)); err != nil && s.log != nil {
-		s.log.Warn("failed to enforce refresh token session limit", zap.String("user_id", rt.UserID), zap.Error(err))
+	// 「最大同时登录终端」只约束未绑定设备会话的旧客户端。
+	//
+	// 移动端每台设备有独立认证会话，刷新令牌归属该会话；如果仍按用户统一
+	// 裁剪活跃令牌，第 N+1 台设备登录（或任一设备刷新）就会把最早那台设备
+	// 的刷新令牌标记为已撤销，那台设备下次刷新收到 SESSION_REVOKED，被迫
+	// 重新登录。设备数量由设备策略单独约束，不能靠撤销刷新令牌实现。
+	if rt.AuthSessionID == "" {
+		if err := s.repo.RefreshToken.RevokeOldestActiveLegacyByUserID(ctx, rt.UserID, s.maxActiveRefreshTokens(ctx)); err != nil && s.log != nil {
+			s.log.Warn("failed to enforce refresh token session limit", zap.String("user_id", rt.UserID), zap.Error(err))
+		}
 	}
 	return nil
 }