| QUANTUM HI-TECH (HK) MEDICINE LIMITED | Private company limited by shares | Live |
| QUANTUM OPTOELECTRONIC (HK) LIMITED | Private company limited by shares | Live |
| QUANTUM PRODUCTIONS (HK) LIMITED | Private company limited by shares | Dissolved |
| QUANTUM PACIFIC RESOURCES (HK) LIMITED | Private company limited by shares | Dissolved |
| Quantum Lighting Technologies (HK), Limited | Private company limited by shares | Live |
| New Quantum Technology (HK) Limited | Private company limited by shares | Live |
| QUANTUM INNOVATION (HK) TECHNOLOGY LIMITED | Private company limited by shares | Live |
| UNIVERSAL QUANTUM ENERGY (HK) LIMITED | Private company limited by shares | Live |
| Quantum Holding Company Limited | Private company limited by shares | Live |
| QUANTUM HOLDINGS LIMITED | Private company limited by shares | Live |
| QUANTUM NZ HOLDINGS LIMITED | Private company limited by shares | Dissolved |
| On Quantum Holdings Limited | Private company limited by shares | Live |
| QUANTUM HOLDINGS HK LIMITED | Private company limited by shares | Live |
| CHINA QUANTUM HOLDINGS LIMITED | Private company limited by shares | Live |
| QUANTUM DESIGNS (HOLDINGS) LIMITED | Private company limited by shares | Dissolved |
| QUANTUM HOLDINGS (FAR EAST) LIMITED | Private company limited by shares | Dissolved |
| Quantum engineering holdings Limited | Private company limited by shares | Live |
| Quantum Equilibrium Holdings Limited | Private company limited by shares | Live |
| Quantum Financial Holdings Limited | | Live |
| Quantum Gravity Financial Holdings Limited | Private company limited by shares | Live |
| Quantum Global Payment Holdings Limited | Private company limited by shares | Live |
| QUANTUM GLOBAL SUMMIT HOLDINGS LIMITED | Private company limited by shares | Live |
| Quantum LEEP Group Holdings Company Limited | Private company limited by shares | Live |
| QUANTUM HOLDINGS (HONG KONG) LIMITED | Private company limited by shares | Dissolved |
| Quantum Hong Kong Holdings Company Limited | Private company limited by shares | Live |
| CHINA QUANTUM INDUSTRIAL HOLDINGS GROUP LIMITED | Private company limited by shares | Live |
| QUANTUM INVESTMENT HOLDINGS LIMITED | Private company limited by shares | Live |
| QUANTUM SPORTS HOLDINGS LIMITED | Private company limited by shares | Dissolved |
| Quantum Value Holdings Limited | Private company limited by shares | Live |
| QUANTUM HOLISTIC HEALTH CENTRE LIMITED | Private company limited by shares | Live |
| HONG KONG QUANTUM COSMETICS CO., LIMITED | Private company limited by shares | Live |
| Quantum Design Hong Kong Limited | Private company limited by shares | Live |
| Quantum Group Solar ( Hong Kong ) Limited | Private company limited by shares | Dissolved |
| HONG KONG QUANTUM HEALTH LIMITED | Private company limited by shares | Live |
| QUANTUM HONG KONG LIMITED | Private company limited by shares | Dissolved |
| QUANTUM (HONG KONG) LIMITED | Private company limited by shares | Live |
| Quantum 3D Hong Kong Limited | Private company limited by shares | Live |
| Hong Kong Quantum AI Lab Limited | Company limited by guarantee | Live |
| QUANTUM ENTERPRISE (HONG KONG) LIMITED | Private company limited by shares | Live |
| Quantum Healthcare Hong Kong Limited | Private company limited by shares | Live |
| Quantum Innovations (Hong Kong) Limited | | Live |
| First Quantum Resources (Hong Kong) Limited | Private company limited by shares | Live |
| Quantum HiTech Technology (Hong Kong) Limited | Private company limited by shares | Live |
| Quantum Research Technology (Hong Kong) Limited | | Live |
| Quantum Group Land ( Hong Kong ) Limited | Private company limited by shares | Dissolved |
| Luenmei Quantum (Hong Kong) Limited | Private company limited by shares | Live |
| Quantum OTEC ( Hong Kong ) Limited | Private company limited by shares | Dissolved |
| HONG KONG QUANTUM PHONICS LIMITED | | Live |
| Quantum Pigeon Hong Kong Limited | Private company limited by shares | Live |
| Quantum Property Hong Kong Limited | Private company limited by shares | Live |
| Quantum Gan Quan (Hong Kong) Limited | Private company limited by shares | Dissolved |
| QUANTUM SAILS HONG KONG LIMITED | Private company limited by shares | Live |
| QUANTUM SEAFOODS (HONG KONG) LIMITED | Private company limited by shares | Live |
| Quantum Storage (Hong Kong) Limited | Private company limited by shares | Live |
| HONG KONG QUANTUM TECH LIMITED | Private company limited by shares | Live |
| HONG KONG BO TONG QUANTUM COMPANY LIMITED | Private company limited by shares | Dissolved |
| Quantum Video (Hong Kong) Limited | | Live |
| HONGKONG QUANTUM LIMITED | Private company limited by shares | Live |
| Quantum Beauty (HongKong) Limited | | Live |
| Quantum Capital (HongKong) Limited | Private company limited by shares | Live |
| Hongkong Quantum International Co., Limited | Private company limited by shares | Live |
| HONGKONG QUANTUM INTERNATIONAL INVESTMENT CO., LIMITED | | Live |
| HONGKONG QUANTUM ELECTRON SCIENCE CO., LIMITED | Private company limited by shares | Dissolved |
| HONGKONG HUAREN QUANTUM SCIENCE FEDERATION LIMITED | Private company limited by shares | Live |
| QUANTUM (HONGKONG) FINANCIAL RESEARCH INSTITUTE LIMITED | Private company limited by shares | Live |
| QUANTUM (HONGKONG) FORWARDING LIMITED | Private company limited by shares | Live |
| HONGKONG QUANTUM SKY GROUP LIMITED | Private company limited by shares | Live |
| GS Quantum (HongKong) Group Co., Limited | Private company limited by shares | Live |
| HONGKONG QUANTUM COMPOUND INVESTMENT GROUP LIMITED | Private company limited by shares | Live |
| HONGKONG QUANTUM HOLDING LIMITED | Private company limited by shares | Live |
| Quantum Industrial (HongKong) Limited | Private company limited by shares | Live |
| HongKong Quantum Industrial International Limited | Private company limited by shares | Live |
| HongKong Quantum Investment Management Co., Limited | Private company limited by shares | Live |
| HONGKONG QUANTUM RACING COMPANY LIMITED | Private company limited by shares | Live |
| Quantum Surgical HongKong Co. Limited | | Live |
| QUANTUM TECHNOLOGY (HONGKONG) COMPANY LIMITED | Private company limited by shares | Live |
| HONGKONG QUANTUM TECHNOLOGY GROUP LIMITED | Private company limited by shares | Dissolved |
| HONGKONG GUANGWU QUANTUM TECHNOLOGY LIMITED | Private company limited by shares | Live |
| QUANTUM HORTICULTURE LIMITED | Private company limited by shares | Dissolved |
| QUANTUM HOTELS LIMITED | Private company limited by shares | Live |
| QUANTUM HOUSE SURVEYORS LIMITED | Private company limited by shares | Dissolved |
| Quantum House Trading Limited | Private company limited by shares | Live |
| Quantum Human Capital Limited | Private company limited by shares | Live |
| QUANTUM HYDROGEN LIMITED | Private company limited by shares | Live |
| Quantum Icloud Limited | Private company limited by shares | Live |
| Quantum MRI and Imaging Centre Limited | Private company limited by shares | Live |
| QUANTUM STRATEGIC INCORPORATION LIMITED | Private company limited by shares | Live |
| ATP QUANTUM INDEX CONSULTANTS LIMITED | Private company limited by shares | Dissolved |
| QUANTUM INDUSTRIAL CO. LIMITED | Private company limited by shares | Dissolved |
| QUANTUM INDUSTRIAL LIMITED | Private company limited by shares | Live |
| QUANTUM INDUSTRIAL (CHINA) LIMITED | Private company limited by shares | Live |
| Quantum Industry Limited | Private company limited by shares | Dissolved |
| INFINITY QUANTUM HOLDING LIMITED | | Live |
| Quantum information Corporation Limited | Private company limited by shares | Live |
| Quantum Innovation Limited | Private company limited by shares | Live |
| Quantum Computing Innovation Company Limited | | Live |
| Quantum Innovations Limited | | Live |
| Quantum Intelligence Limited | Private company limited by shares | Live |
| QUANTUM INTELLIGENCE (HONGKONG) CO., LIMITED | Private company limited by shares | Live |
| QUANTUM MARKET INTELLIGENCE LIMITED | Private company limited by shares | Live |