| QUANTUM CREEK TIRES LIMITED | Private company limited by shares | Live |
| QUANTUM TRADE COMPANY LIMITED | Private company limited by shares | Dissolved |
| QUANTUM TRADING COMPANY LIMITED | Private company limited by shares | Dissolved |
| QUANTUM TRADING LIMITED | Private company limited by shares | Live |
| Quantum Trading Limited | Private company limited by shares | Live |
| Quantum Capital Trading Limited | Private company limited by shares | Live |
| QUANTUM METAL TRADING LIMITED | Private company limited by shares | Live |
| Quantum Wisdom Trading Limited | | Live |
| QUANTUM TRAINING LIMITED | Private company limited by shares | Live |
| Quantum Trust Limited | | Live |
| UNIVERSAL QUANTUM ENERGY LIMITED | Private company limited by shares | Live |
| Universal Holographic Quantum Extracts Limited | Private company limited by shares | Live |
| Quantum Universe Limited | | Live |
| Quantum Universe (HK) Limited | Private company limited by shares | Live |
| Quantum Capital Unlimited HK Limited | Private company limited by shares | Live |
| Vaultavo Quantum Limited | | Live |
| Quantum Ventures Limited | | Live |
| Quantum Mining Ventures Limited | Private company limited by shares | Live |
| Quantum Vortex Limited | Private company limited by shares | Live |
| Quantum Water Technologies Limited | Private company limited by shares | Live |
| QUANTUM WINSOME LIMITED | Private company limited by shares | Dissolved |
| QUANTUM WORLD LIMITED | Private company limited by shares | Live |
| QuantumAI Limited | | Live |
| QUANTUMAX INVESTMENTS LIMITED | Private company limited by shares | Dissolved |
| AMCHI QUANTUMBIO SCIENCE (HK & MACAU) LIMITED | Private company limited by shares | Live |
| Quantumbit Limited | Private company limited by shares | Live |
| Quantumbro Co., Limited | | Live |
| QUANTUMCODE LIMITED | | Live |
| QuantumCyte Technology Limited | Private company limited by shares | Live |
| Quantumdots Limited | | Live |
| QuantumFabless Limited | Private company limited by shares | Live |
| QUANTUMFACTORY CO. LIMITED | Private company limited by shares | Live |
| QuantumFlow Limited | | Live |
| QuantumForge Limited | | Live |
| QUANTUMIZE LIMITED | | Live |
| QuantumKDB Limited | Private company limited by shares | Live |
| Quantumlink Limited | Private company limited by shares | Dissolved |
| QuantumMeta Limited | | Live |
| QUANTUMMIND SOLUTIONS HONG KONG LIMITED | | Live |
| QuantumNova Limited | | Live |
| QuantumPharm Limited | Private company limited by shares | Live |
| QUANTUMPLAN LIMITED | Private company limited by shares | Dissolved |
| QuantumPulse Enterprises Limited | | Live |
| Hong Kong QuantumRealmTech Limited | | Live |
| QuantumS Limited -The- | Private company limited by shares | Live |
| QuantumSailing Technologies Limited | | Live |
| QUANTUMSIL LIMITED | Private company limited by shares | Live |
| Quantumsis Co., Limited | | Live |
| Quantumsolve Limited | | Live |
| Quantumspace Limited | | Live |
| SHENZHEN QUANTUMSTAR TECHNOLOGY CO., LIMITED | Private company limited by shares | Dissolved |
| QuantumTech Limited | | Live |
| Carl Quantum-Tech Co., Limited | | Live |
| QUANTUMTEK CO., LIMITED | Private company limited by shares | Live |
| Quantumtime Limited | Private company limited by shares | Live |
| QUANTUMTRADE LIMITED | | Live |
| QuantumTrust Solutions Limited | | Live |
| QuantumTX Hong Kong Limited | | Live |
| Quantumverse Limited | | Live |
| QuantumWhale Limited | | Live |