- Obeegadoo Mervin
- Oberle Frank
- Oborzyn ́ski Krzysztof
- Odet Christophe
- Odille F
- Oellers Michel
- Ognard Julien
- Ogor Robert
- Ohno Hideo
- Oikonomou George
- Okamoto Satoru
- Olaszi Peter
- Olivares Amaro Marisnel Carolina
- Olivier Christian
- Olivier Christian
- Ollivier Benjamin
- Ollivier Benjamin
- Olteanu Alexandru-Liviu
- Olvera Irigoyen Oscar
- Olvera Irigoyen Oscar
- Onana V.P.
- Onete Cristina
- Onizawa Naoya
- Oquendo Maria
- Orda Ariel
- Ordonez John Richard
- Orgerie Anne-Cécile
- Oriot Hélène
- Ormrod Janet
- Oro Daniel
- Orozco Torrentera Julio Enrique
- Ortalo R.
- Ortega Felipe
- Ortega-Ruiz Jose A.
- Ortiz Guzman John Erick
- Ortiz Guzman John Erick
- Orus-Perez Raul
- Osswald Christophe
- Otnes Roald
- Ouarda Wael
- Ouarraou Mohamed
- Ouasli Faicel
- Ouattara F.
- Ouattara Frédéric Martial
- Ouelha Samir
- Ouertani Karim
- Ouertani Karim
- Oueslati Sameh
- Oularbi Mohamed Rabie
- Oularbi Mohamed Rabie
- Oularbi Mohamed Rabie
- Ould Cheikh Mouhamedou Youssouf
- Ould Cheikh Mouhamedou Youssouf
- Ould Mohamed Sidi
- Oulmakhzoune Said
- Oulmakhzoune Said
- Ourahmoune Amel
- Ourraou Mohamed
- Ouvradou Gérald
- Ouvradou Gwénaelle
- Ouya Ange
- Ouyang Junlin
- Ouy Julien
- Ouzzif Meryem
- Ovejero-García Santiago
- Owezarski Philippe
- Oyedapo Olufemi
- Oyen Wim J. G.
- Oyen Wim J.G