| Hong Kong Medical Optometry Center Limited | | Live |
| HONG KONG LINMU OPTOMETRY RESEARCH INSTITUTE COMPANY LIMITED | Private company limited by shares | Live |
| JJM OPTOMETRY TECHNOLOGY HONG KONG LIMITED | Private company limited by shares | Dissolved |
| Optomodo Limited | Private company limited by shares | Live Commenced dormancy on 16-Nov-2015 |
| OPTON (CHINA) LIMITED | Private company limited by shares | Live |
| OPTON HONG KONG LIMITED | Private company limited by shares | Live |
| OPTON (FUJIAN) OPTICS CO., LIMITED | Private company limited by shares | Live |
| OptOnc Health Management Co., Limited | Private company limited by shares | Live |
| OPTOPLEX LIMITED | Private company limited by shares | Live |
| SINTECH OPTOPOWER LIMITED | Private company limited by shares | Live |
| OPTO-PRO ENTERPRISES LIMITED | Private company limited by shares | Dissolved |
| OPTOPROBE LIMITED | Private company limited by shares | Live |
| OPTOR INVESTMENT LIMITED | Private company limited by shares | Live |
| OPTOROUTE HK LIMITED | Private company limited by shares | Live |
| OPTORUNNING OPTOELECTRONIC TECHNOLOGY CO., LIMITED | Private company limited by shares | Live |
| OPTOSCREEN CORPORATION LIMITED | Private company limited by shares | Live |
| Orient Opto-Semiconductors Corporation (Hong Kong) Limited | Private company limited by shares | Dissolved |
| OPTO-SENSOR LIMITED | Private company limited by shares | Live |
| Optostars Group Limited | Private company limited by shares | Live |
| OPTOSTOR PAPYRUS LIMITED | Private company limited by shares | Dissolved |
| OPTOSUN LED TECHNOLOGY COMPANY LIMITED | Private company limited by shares | Live |
| OPTOSUN TECHNOLOGY LIMITED | Private company limited by shares | Live |
| OPTOSUPPLY LIMITED | Private company limited by shares | Live |
| OPTOSUPPLY ELECTRICAL LIMITED | Private company limited by shares | Live |
| OPTOSUPPLY ELECTRONICS LIMITED | Private company limited by shares | Live |
| OPTOSUPPLY ENERGY LIMITED | Private company limited by shares | Dissolved |
| OPTOSUPPLY INTERNATIONAL LIMITED | Private company limited by shares | Dissolved |
| OPTOSUPPLY TECHNOLOGIES LIMITED | Private company limited by shares | Live |
| J&K OPTOTEC CO., LIMITED | Private company limited by shares | Live |
| OPTOTEC HONG KONG LIMITED | Private company limited by shares | Dissolved |
| OPTOTEC MATERIALS CO., LIMITED | Private company limited by shares | Live |
| OPTOTECH ASIA LIMITED | Private company limited by shares | Live |
| CHINA OPTOTECH COMPANY LIMITED | Private company limited by shares | Live |
| DANA OPTOTECH LIMITED | Private company limited by shares | Live |
| EVER SHINING OPTOTECH COMPANY LIMITED | Private company limited by shares | Live |
| JTU OptoTech (Hong Kong) Co. Limited | Private company limited by shares | Dissolved |
| JIMEI OPTOTECH LIMITED | Private company limited by shares | Live |
| HOEOO OPTOTECH (HONG KONG) CO., LIMITED | Private company limited by shares | Live |
| WISE OPTOTECH LIMITED | Private company limited by shares | Live |
| RUNWELL OPTO-Telecom Limited | Private company limited by shares | Live |
| HONGKONG OPTOTHERMAL EXPLOITATION LIMITED | Private company limited by shares | Dissolved |
| NITTO OPTOTRONICS LIMITED | Private company limited by shares | Live |
| Optovance Limited | Private company limited by shares | Live |
| OPTOVISIONS CO. LIMITED | Private company limited by shares | Live |
| OPTOVOZOFF LIMITED | Private company limited by shares | Live |
| Optovue Hong Kong Company Limited | Private company limited by shares | Live |
| OPTOWAVES (HONG KONG) LIMITED | Private company limited by shares | Dissolved |
| OPTO-WIN TECHNOLOGY LIMITED | Private company limited by shares | Live |
| ADC OPTP COMPANY LIMITED | Private company limited by shares | Live |
| OPTREX HONG KONG COMPANY LIMITED | Private company limited by shares | Dissolved |
| Optrex Hong Kong Company Limited | Private company limited by shares | Dissolved |
| OPTRIS ASIA LIMITED | Private company limited by shares | Live |
| OPTRIX LIMITED | Private company limited by shares | Live |
| OPTRON H.K LIMITED | Private company limited by shares | Live |
| OPTRON TECHNOLOGY HK LIMITED | Private company limited by shares | Live |
| FOSINCE OPTRONEC (HK) LIMITED | Private company limited by shares | Dissolved |
| ADVANCED OPTRONIC DEVICES (ASIA) CO. LIMITED | Private company limited by shares | Live |
| JC OPTRONICS LIMITED | Private company limited by shares | Dissolved |
| M.K Optronics HK Limited | Private company limited by shares | Dissolved |
| T&Q OPTRONICS LIMITED | Private company limited by shares | Live Commenced dormancy on 18-Mar-2016 |
| INT Optronics Limited | Private company limited by shares | Live |
| OPTRONICS LIMITED | Private company limited by shares | Live |
| Advanced Optronics Limited | | Live |
| GLORY OPTRONICS LIMITED | Private company limited by shares | Live |
| PACIFIC GOAL OPTRONICS LIMITED | Private company limited by shares | Live |
| TAI LONG OPTRONICS LIMITED | Private company limited by shares | Live |
| MEGA POWER OPTRONICS LIMITED | Private company limited by shares | Dissolved |
| PROTECH OPTRONICS COMPANY LIMITED | Private company limited by shares | Dissolved |
| SKYTEK OPTRONICS LIMITED | Private company limited by shares | Live |
| SOUTH HAOYU OPTRONICS LIMITED | Private company limited by shares | Live |
| JD OPTRONIX LIMITED | Private company limited by shares | Live |
| OPTSATION LIMITED | Private company limited by shares | Live |
| OPTTECH LIMITED | Private company limited by shares | Dissolved |
| OPT-TECH MANUFACTURING LIMITED | Private company limited by shares | Live |
| OPTUM LIMITED | Private company limited by shares | Dissolved |
| Optum Limited | Private company limited by shares | Live |
| OPTURN COMPANY LIMITED | Private company limited by shares | Live |
| Optus Limited | Private company limited by shares | Live |
| OPTYPHAR LIMITED | Private company limited by shares | Dissolved |