| Starlight Quest Limited | Private company limited by shares | Dissolved |
| STUDENT QUEST LIMITED | Private company limited by shares | Live |
| SUNNY QUEST LIMITED | Private company limited by shares | Live |
| TALENT QUEST LIMITED | Private company limited by shares | Live |
| TALENT QUEST INVESTMENT LIMITED | Private company limited by shares | Live |
| Quest Tech Limited | Private company limited by shares | Live |
| Quest Technology Limited | Private company limited by shares | Live |
| Trade Quest Limited | Private company limited by shares | Dissolved |
| QUEST TRADING COMPANY LIMITED | Private company limited by shares | Live |
| TREASURE QUEST LIMITED | Private company limited by shares | Live |
| TREASURE QUEST CHINA COMPANY LIMITED | Private company limited by shares | Dissolved |
| ULTIMATE QUEST LIMITED | Private company limited by shares | Dissolved |
| San Quest (UN) Limited | Private company limited by shares | Live |
| VISION QUEST LIMITED | Private company limited by shares | Live |
| QUESTA LIMITED | Private company limited by shares | Live |
| Questa Trade Limited | Private company limited by shares | Live |
| QUESTAK LIMITED | Private company limited by shares | Dissolved |
| QUESTANO HK LIMITED | | Live |
| QUESTAR LIMITED | Private company limited by shares | Live |
| QUESTAR-MARCOM ASIA LIMITED | Private company limited by shares | Dissolved |
| QUESTEC INTERNATIONAL LIMITED | Private company limited by shares | Dissolved |
| QUESTECH INDUSTRIAL LIMITED | Private company limited by shares | Dissolved |
| QUESTER CO., LIMITED | Private company limited by shares | Live |
| QUESTER ENTERPRISE CO., LIMITED | Private company limited by shares | Live |
| Quester Education (Kowloon) Limited | Private company limited by shares | Live |
| QUESTER CAPITAL (HK) LIMITED | Private company limited by shares | Live |
| Quester International Limited | Private company limited by shares | Live |
| QUESTER INTERNATIONAL PETROLEUM EQUIPMENT LIMITED | Private company limited by shares | Live |
| Quester Securities (HK) Limited | | Live |
| QUESTEX LIMITED | Private company limited by shares | Dissolved |
| Questex Asia Limited | Private company limited by shares | Live |
| QUESTHOLM LIMITED | Private company limited by shares | Live |
| QUESTIME WATCH INDUSTRY LIMITED | Private company limited by shares | Live |
| QUESTIMPACT LIMITED | Private company limited by shares | Live |
| QUESTION MARK COMPANY LIMITED | Private company limited by shares | Live |
| FUN QUESTION SPORTS LIMITED | Private company limited by shares | Live |
| QUESTION THEREFORE LIMITED | Private company limited by shares | Live |
| Weak 2 Question Company Limited | | Live |
| Questionify Limited | | Live |
| QuestionInsurance.com Limited | Private company limited by shares | Live |
| QUESTIONSMART LIMITED | Private company limited by shares | Live |
| QUESTLANE INTERNATIONAL LIMITED | Private company limited by shares | Dissolved |
| QuestLED Co., Limited | Private company limited by shares | Live |
| QuestMaker Advergaming Limited | Private company limited by shares | Dissolved |
| QuestMark Asia Limited | Private company limited by shares | Live |
| QUESTMORE LIMITED | Private company limited by shares | Dissolved |
| QUESTO LIMITED | Private company limited by shares | Dissolved |
| QUESTO DESIGN LIMITED | Private company limited by shares | Dissolved |
| QUESTO EXPORT LIMITED | Private company limited by shares | Dissolved |
| Questopia Entertainment Limited | | Live |
| QUESTOR LIMITED | Private company limited by shares | Dissolved |
| QUESTOR MANAGEMENT LIMITED | Private company limited by shares | Live |
| QUESTOR WOOD INDUSTRY LIMITED | Private company limited by shares | Dissolved |
| QUESTPOINT LIMITED | Private company limited by shares | Dissolved |
| QuestPX Limited | | Live |
| Questro Investment Limited | Private company limited by shares | Dissolved |
| Questronic HK Limited | Private company limited by shares | Dissolved |
| QUESTWAY LIMITED | Private company limited by shares | Dissolved |
| QUESTWELL LIMITED | Private company limited by shares | Dissolved |