| SIEN ON SHIPPING COMPANY LIMITED | Private company limited by shares | Dissolved |
| SIENA LIMITED | Private company limited by shares | Dissolved |
| Siena 28 Limited | Private company limited by shares | Live |
| SIENA LIMITED | Company limited by guarantee | Live Commenced dormancy on 05-Dec-2013 |
| SIENAR LIMITED | Private company limited by shares | Live |
| SienaRicci Limited | Private company limited by shares | Live |
| Sienboyuan (Hong Kong) Technology Co., Limited | | Live |
| Space Sience Trading Limited | Private company limited by shares | Dissolved |
| SIENG CHIN TRADING COMPANY, LIMITED | Private company limited by shares | Dissolved |
| SIENHUA GROUP LIMITED | Private company limited by shares | Live |
| H. SIENMIN & SONS (HONG KONG) LIMITED | Private company limited by shares | Dissolved |
| SIENNA LIMITED | Private company limited by shares | Live |
| Sienna & Ian Co. Limited | Private company limited by shares | Live |
| SIENNA CAPITAL ASIA LIMITED | Private company limited by shares | Live |
| Sienna Charles Limited | Private company limited by shares | Live |
| JASPER DESERT SIENNA CONSULTING LIMITED | Private company limited by shares | Live |
| SIENNA CORPORATION LIMITED | Private company limited by shares | Dissolved |
| RAW SIENNA DEVELOPMENT LIMITED | Private company limited by shares | Dissolved |
| Sienna Estates Limited | Private company limited by shares | Live |
| SIENNA FOREMOST COMPANY LIMITED | Private company limited by shares | Live |
| SIENNA HOLDINGS LIMITED | Private company limited by shares | Live |
| SIENNA HOME (HK) LIMITED | Private company limited by shares | Live |
| Hong Kong Sienna Trading Limited | Private company limited by shares | Live |
| SIENNA INTERNATIONAL (H.K.) LIMITED | Private company limited by shares | Live |
| Sienna International Trading Limited | Private company limited by shares | Live |
| SIENNA MICRO GROUP LIMITED | | Live |
| SIENNA MICRO TECHNOLOGY CO., LIMITED | Private company limited by shares | Live |
| SIENNA SERVICES LIMITED | Private company limited by shares | Live |
| SIENNA SNAKY LIMITED | Private company limited by shares | Live |
| Sienna Trading Company Limited | Private company limited by shares | Live |
| SIENO ITALY LIMITED | Private company limited by shares | Dissolved |
| SIENOC HONG KONG LIMITED | Private company limited by shares | Live |
| SIENPENG (INTERNATIONAL) LIMITED | Private company limited by shares | Dissolved |
| SHENZHEN SIENTA INDUSTRY CO., LIMITED | Private company limited by shares | Live |
| SIENTZ TRADING CO., LIMITED | Private company limited by shares | Live |
| Sienwell Electronic Co., Limited | Private company limited by shares | Live |