| Name | Functions  | Event Dates | Events | Resources | ||
|---|---|---|---|---|---|---|
| Frej Obenius | Sound Designer | 2015 | 1 | |||
| Yu Okada | Sound Designer | 2009 | 1 | |||
| Erna Ophaug | Sound Designer | 1953 - 2006 | 4 | |||
| Akira Oyamada | Sound Designer | 1998 | 1 | |||
| Matt Otto | Sound Designer | 2017 | 1 | |||
| Makoto Obara | Sound Designer | 1990 | 1 | |||
| João Ricardo Barros Oliveira | Sound Designer | 2002 | 3 | |||
| Adolf Otremba | Translator | 1882 - 1883 | 3 | |||
| Victor Ottmann | Translator | 1901 - 1902 | 9 | 1 | ||
| Piero Ottolini | Translator | 1905 - 1906 | 4 | |||
| Sanjiro Ohta | Translator | 1914 | 1 | |||
| Ladislav Obuch | Translator | 1955 - 2018 | 13 | |||
| Ruth Orthmann | Translator | 1994 | 1 | |||
| Vidal de Oliveira | Translator | 1949 - 1994 | 6 | |||
| Hermann Otto | Translator | 2002 | 1 | |||
| Girija Oak | Translator | 2009 | 1 | |||
| Marcel Otten | Translator | 2012 - 2013 | 29 | |||
| Kazuo Okano | Translator | 1959 | 1 | |||
| Anders Orbeck | Translator | 1936 - 2018 | 3 | |||
| Yılmaz Onay (Yilmaz Onay) | Translator | 2007 | 1 | |||
| Ragnar Olsen | Translator | 2018 | 10 | |||
| Milan Ogrizović | Translator | 1913 | 1 | |||