- OBADI MOHAMMED ESMAIL AHMED
- OFOSU OKOTO ERIC
- OLEG VARVYANSKIY
- OH HYUNMAN
- ORFEO FINOCCHI
- OH SUK KYUNG
- OH SHUNKO
- OH BUMSUG
- OYIEYO BILDAD ONGONGA
- OLIUDDIN MD
- OLEKSANDR SLIVINSKYY
- OOI PEI HOU
- ONG KAE LUEN
- ONG BENG CHOO
- ONG SHENG KEAT
- ONG KAR CHING
- OU ZHAN HONG
- OUYANG XIAOLONG
- ORAEVSKY ALEXANDER ANATOLY
- OH CHONG SOO
- OGASAWARA AKIRA
- OTSUJI ATSUO（大辻纯生）
- Olivier BERGER
- ONG KANG WEI
- ONO HIDEHIKO（大野 英彦）
- OK SEON KIM
- OWEN JAMES WILSON
- ONO SHIEN
- OMUCHILO RODNEY MOSES MUYERA
- Ofer Oveed