| KEYLINE LIMITED | Private company limited by shares | Live |
| KEYLINE CHEMICAL LIMITED | Private company limited by shares | Dissolved |
| Keyline Composites Limited | Private company limited by shares | Live |
| KEYLINE CONSULTANTS LIMITED | Private company limited by shares | Dissolved |
| KEYLINE CORPORATION LIMITED | Private company limited by shares | Dissolved |
| Hongkong Keyline Health Limited | | Live |
| KEYLINE INDUSTRIAL LIMITED | Private company limited by shares | Live |
| KEYLINE INTERNATIONAL GROUP LIMITED | Private company limited by shares | Live |
| KEYLINE INTERNATIONAL (H.K.) LIMITED | Private company limited by shares | Dissolved |
| KEYLINE INVESTMENTS LIMITED | Private company limited by shares | Dissolved |
| KEYLINE MANAGEMENT COMPANY LIMITED | Private company limited by shares | Dissolved |
| KEYLINE NEW-TECH (HONG KONG) CO., LIMITED | Private company limited by shares | Live |
| KEYLINE TRADING LIMITED | Private company limited by shares | Live Commenced dormancy on 22-Nov-1994 |
| Keyline Holding & Trading Limited | Private company limited by shares | Live |