diff --git a/cmd/telesrv/main.go b/cmd/telesrv/main.go
index 6632746d..720fabf4 100644
--- a/cmd/telesrv/main.go
+++ b/cmd/telesrv/main.go
@@ -443,6 +443,11 @@ func run(logger *zap.Logger) error {
 			zap.Int("blobs", stats.Blobs),
 		)
 	}
+	if seeded, err := filesService.SeedOfficialSystemAvatar(ctx); err != nil {
+		return fmt.Errorf("seed official system avatar: %w", err)
+	} else if seeded {
+		logger.Info("官方系统账号头像种子导入完成", zap.Int64("photo_id", domain.OfficialSystemUserPhotoID))
+	}
 	if stats, err := filesService.WarmCaches(ctx); err != nil {
 		logger.Warn("媒体资源缓存预热失败", zap.Error(err))
 	} else if stats.StickerSets > 0 || stats.Documents > 0 || stats.Blobs > 0 {
diff --git a/deploy/migrations/0086_owpengram_system_account_brand.down.sql b/deploy/migrations/0086_owpengram_system_account_brand.down.sql
new file mode 100644
index 00000000..482a63b0
--- /dev/null
+++ b/deploy/migrations/0086_owpengram_system_account_brand.down.sql
@@ -0,0 +1,3 @@
+UPDATE public.users
+SET first_name = 'Telegram', username = 'telegram', updated_at = now()
+WHERE id = 777000;
diff --git a/deploy/migrations/0086_owpengram_system_account_brand.up.sql b/deploy/migrations/0086_owpengram_system_account_brand.up.sql
new file mode 100644
index 00000000..23f650f6
--- /dev/null
+++ b/deploy/migrations/0086_owpengram_system_account_brand.up.sql
@@ -0,0 +1,8 @@
+-- Rebrand the built-in official system account (777000) from the upstream
+-- gramsrv default "Telegram"/@telegram to this fork's own identity. Existing
+-- databases already seeded by migration 0001 need this as a follow-up
+-- UPDATE; migration 0001 itself is never replayed on an already-migrated
+-- database.
+UPDATE public.users
+SET first_name = 'OwpenGram', username = 'owpengram', updated_at = now()
+WHERE id = 777000;
diff --git a/internal/app/files/seedassets/owpengram_system_avatar.png b/internal/app/files/seedassets/owpengram_system_avatar.png
new file mode 100644
index 00000000..32339056
Binary files /dev/null and b/internal/app/files/seedassets/owpengram_system_avatar.png differ
diff --git a/internal/app/files/system_avatar_seed.go b/internal/app/files/system_avatar_seed.go
new file mode 100644
index 00000000..2b77f908
--- /dev/null
+++ b/internal/app/files/system_avatar_seed.go
@@ -0,0 +1,44 @@
+package files
+
+import (
+	"context"
+	_ "embed"
+	"time"
+
+	"telesrv/internal/domain"
+)
+
+//go:embed seedassets/owpengram_system_avatar.png
+var officialSystemAvatarPNG []byte
+
+// SeedOfficialSystemAvatar idempotently seeds the built-in official system
+// account's (777000) profile photo from the bundled brand logo, writing it
+// under the fixed domain.OfficialSystemUserPhotoID so the photo/blob layer
+// and the pure domain.OfficialSystemUser() struct literal stay in sync
+// across restarts. Returns true if it actually wrote a new photo.
+func (s *Service) SeedOfficialSystemAvatar(ctx context.Context) (bool, error) {
+	photoID := domain.OfficialSystemUserPhotoID
+	if existing, found, err := s.media.GetPhoto(ctx, photoID); err != nil {
+		return false, err
+	} else if found {
+		domain.SetOfficialSystemUserAvatar(existing.DCID, domain.StrippedFromSizes(existing.Sizes))
+		return false, nil
+	}
+	sizes, err := s.putPhotoStaticSizes(ctx, photoID, officialSystemAvatarPNG, photoSizeSpecsForAvatar(officialSystemAvatarPNG))
+	if err != nil {
+		return false, err
+	}
+	photo := domain.Photo{
+		ID:            photoID,
+		AccessHash:    domain.OfficialSystemUserPhotoAccessHash,
+		FileReference: randomFileReference(),
+		Date:          int(time.Now().Unix()),
+		DCID:          s.dc,
+		Sizes:         sizes,
+	}
+	if err := s.media.PutPhoto(ctx, photo); err != nil {
+		return false, err
+	}
+	domain.SetOfficialSystemUserAvatar(photo.DCID, domain.StrippedFromSizes(photo.Sizes))
+	return true, nil
+}
diff --git a/internal/domain/system.go b/internal/domain/system.go
index b1f6a399..dfc65911 100644
--- a/internal/domain/system.go
+++ b/internal/domain/system.go
@@ -3,6 +3,11 @@ package domain
 const (
 	// OfficialSystemUserID 是 Telegram 兼容客户端识别的官方系统账号。
 	OfficialSystemUserID int64 = 777000
+	// OfficialSystemUserPhotoID/AccessHash 是该账号头像 photo 的固定 id，
+	// 与 files.Service.SeedOfficialSystemAvatar 种子写入的行保持一致，
+	// 确保跨重启后 OfficialSystemUser() 引用的 photo id 稳定不变。
+	OfficialSystemUserPhotoID         int64 = 7770000001
+	OfficialSystemUserPhotoAccessHash int64 = 5837219004471160321
 
 	// BotFatherUserID 是内置 BotFather 账号，与官方 @BotFather 同 ID。
 	BotFatherUserID int64 = 93372553
@@ -21,17 +26,38 @@ const (
 	ChatBotAccessHash int64 = 6332902371644871201
 )
 
+// officialSystemUserPhotoDCID/Stripped 由 files.Service.SeedOfficialSystemAvatar
+// 在启动时通过 SetOfficialSystemUserAvatar 写入一次；写入前 OfficialSystemUser()
+// 不带头像（PhotoID==0），与其它未设置头像的账号行为一致。
+var (
+	officialSystemUserPhotoDCID     int
+	officialSystemUserPhotoStripped []byte
+)
+
+// SetOfficialSystemUserAvatar 记录官方系统账号头像所在的 DC 与内联缩略图字节。
+// 只应在启动阶段、头像 seed 完成后调用一次。
+func SetOfficialSystemUserAvatar(dcID int, stripped []byte) {
+	officialSystemUserPhotoDCID = dcID
+	officialSystemUserPhotoStripped = stripped
+}
+
 // OfficialSystemUser 返回第一阶段内置的官方系统账号。
 func OfficialSystemUser() User {
-	return User{
+	u := User{
 		ID:         OfficialSystemUserID,
 		AccessHash: 6599886787491911851,
 		Phone:      "42777",
-		FirstName:  "Telegram",
-		Username:   "telegram",
+		FirstName:  "OwpenGram",
+		Username:   "owpengram",
 		Verified:   true,
 		Support:    true,
 	}
+	if officialSystemUserPhotoDCID != 0 {
+		u.PhotoID = OfficialSystemUserPhotoID
+		u.PhotoDCID = officialSystemUserPhotoDCID
+		u.PhotoStripped = officialSystemUserPhotoStripped
+	}
+	return u
 }
 
 // BotFatherUser 返回内置 BotFather 账号。username 不以 bot 结尾属种子例外（与官方一致）。