| Name | Functions | Event Dates | Events  | Resources | ||
|---|---|---|---|---|---|---|
| Sarah O´Donnell | Actor | 1987 | 2 | |||
| Josephyne Oliveri | Actor | 1987 | 2 | |||
| Robert Ornbo | Lighting Designer | 1978 - 1987 | 2 | 1 | ||
| Jack O'Brien | Director | 1990 - 2025 | 2 | 1 | ||
| Eva Otto | Actor | 1991 | 2 | |||
| Ulrike Obermüller | Costume Designer | 1991 - 2016 | 2 | |||
| Lotta Ohlsson | Actor | 1990 | 2 | |||
| Kjell Oscarsson | Actor | 1990 | 2 | |||
| Heinz Opfinger | Actor | 1990 - 1991 | 2 | |||
| Victoria Otto | Actor | 1990 | 2 | |||
| Jiří Ornest | Actor | 1988 - 2012 | 2 | |||
| Dietmar Obst | Actor | 1993 - 1999 | 2 | |||
| Annelie Ottosson | Actor | 1993 | 2 | |||
| Ádám Ottlik | Actor | 1996 - 2008 | 2 | 1 | ||
| Carl-Friedrich Oberle | Costume Designer, Designer | 1994 | 2 | |||
| Barney O'Sullivan | Actor | 1976 - 1980 | 2 | |||
| Francis O'Connor | Designer, Set Designer | 2000 - 2023 | 2 | |||
| Thomas Oglesby | Actor | 1977 - 1980 | 2 | 1 | ||
| Marika Ohlsson | Actor | 1997 | 2 | |||
| Ken Ohara | Actor | 1996 - 1997 | 2 | |||
| Inge Olsson | Actor | 1997 | 2 | |||
| Nicholas Olsson | Actor | 1996 - 1997 | 2 | |||
| Edward Ożana | Actor | 1970 - 1975 | 2 | |||
| Stanislav Oubram | Actor | 1969 - 2006 | 2 | |||
| Mieczysław Ostroróg | Actor | 1968 | 2 | |||
| Karen Oettinger | Actor | 1968 | 2 | |||
| Magda Olty | Actor | 1935 - 1941 | 2 | |||
| Kikuko Ogata | Costume Designer | 1968 - 2010 | 2 | |||
| Sándor Oszter | Actor | 1978 - 2007 | 2 | 1 | ||
| Marrit Ohlsson | Actor | 1947 - 1966 | 2 | |||
| Helga Orosz | Actor | 2005 | 2 | |||
| György Orbán | Composer | 1972 - 2002 | 2 | 1 | ||
| Anton Ostrugnaj | Actor | 2002 | 2 | |||
| Marcel Ott | Actor | 2002 | 2 | |||
| Marc Olinger | Actor | 2003 | 2 | |||
| Paul Ocampo | Actor, Dancer | 2001 | 2 | |||
| Marette Oppenberg | Costume Designer | 2003 | 2 | 1 | ||
| Jim O'Brien | Actor | 2004 - 2021 | 2 | 1 | ||
| Terje Olden | Actor | 2004 | 2 | |||
| Andrew David Ostrowski | Lighting Designer | 2005 - 2007 | 2 | |||
| Vayu O'Donnell | Actor | 2005 - 2016 | 2 | |||
| Antónia Oľšavská | Actor | 2012 | 2 | |||