- Onur Dulgeroglu
- Opeyemi Fadipe
- Oriana Calderon
- Osbert Bastani
- Oscar A. Herrera-Restrepo
- Oscar Aguilar
- Oscar Dowson
- Oscar Repping
- Oskar Marko
- Osman Oguz
- Osman Rauf Karaaslan
- Osman Y. Ozaltin
- Osvaldo F. Morera
- Otilia Obodaru
- Owen Wu
- Özalp Özer
- Ozan Candogan
- Ozge Turut
- Ozge Yapar
- Ozgun Caliskan Demirag
