| Name | Functions | Event Dates | Events | Resources  | ||
|---|---|---|---|---|---|---|
| Heinrich Ortmayr | Actor | 1982 | 1 | |||
| Igor Okhlupin (Игорь Охлупин) | Actor | 2013 | 1 | |||
| Carl-Friedrich Oberle | Costume Designer, Designer | 1994 | 2 | |||
| Vidal de Oliveira | Translator | 1949 - 1994 | 6 | |||
| Izabella Olszewska | Actor | 1994 | 1 | |||
| Tim Oliver | Sound Designer | 1994 - 1995 | 3 | |||
| Frances O'Connor | Actor | 1994 | 1 | |||
| Barney O'Sullivan | Actor | 1976 - 1980 | 2 | |||
| Shinji Ogawa | Actor | 1980 | 1 | |||
| Linda Oug | Actor | 1980 | 1 | |||
| Brian O'Donoghue | Lighting Designer | 1980 | 1 | |||
| Paul O'Brien | Actor | 1980 | 1 | |||
| Boris Ostan | Actor | 1994 | 1 | |||
| Jette Ostan Vejrup | Actor | 1994 | 1 | |||
| Francis O'Connor | Designer | 2000 | 1 | |||
| Nobuhisa Ohshima | Actor, Adaptation, Director | 1994 | 3 | |||
| Julia Trevelyan Oman | Designer | 1980 | 1 | |||
| Julia Odegard | Actor | 1980 | 1 | |||
| Ivo Ognjanov | Actor | 1994 | 1 | |||
| Aksel Orav | Actor | 1962 - 1997 | 5 | |||
| Sandra Ortmann | Mask Maker | 1996 | 1 | |||
| Ruth Olsén | Actor | 1995 | 5 | |||
| H. Kevin Opela | Actor | 1996 | 1 | |||
| Christof Oswald | Actor | 1996 | 1 | |||
| Giuseppe Oristânio | Actor | 1997 - 1998 | 3 | |||
| Domingos José Soares de Oliveira | Actor, Adaptation, Director, Lighting Designer, Sound Designer, Translator | 1983 - 1998 | 15 | |||
| Brigitte Oessling | Actor | 1995 | 1 | |||
| David Oldman | Designer | 1996 | 1 | |||
| Bartosz Opania | Actor | 1997 | 1 | |||
| Marika Ohlsson | Actor | 1997 | 2 | |||
| Adriaan Olree | Actor | 1996 | 1 | |||
| Ken Ohara | Actor | 1996 - 1997 | 2 | |||
| Majvor Olsson | Actor | 1997 | 1 | |||
| Kurt Olsson | Actor | 1997 | 1 | |||
| Inge Olsson | Actor | 1997 | 2 | |||
| Yehiel Orgal | Lighting Designer | 1995 | 1 | |||
| Ryoichi Ohkubo | Actor, Director, Translator | 1996 - 2006 | 4 | |||
| Yoko Onizawa | Sound Designer | 1996 | 1 | |||
| Heinz Ostermann | Actor | 1995 | 1 | |||
| Simone Ott | Actor | 1995 | 4 | |||
| Minni Oehl | Actor | 1995 | 6 | |||
| Jakub Ostaszewski | Composer | 1995 | 1 | |||