| O2 Films | — | — | 3 |
| O3 Medya | — | — | 1 |
| Oakshire Productions | — | — | 1 |
 Oberon Cinematogràfica | Barcelona | 1990 | 1 |
| Objectiv Filmstudio | — | — | 1 |
| Oceania Produzioni Internazionali Cinematografiche | — | — | 1 |
 OCN | — | 1995 | 6 |
 OddLot Entertainment | Culver City | 2001 | 1 |
| Odeon | — | — | 1 |
| Odeon Film | Wiesbaden, Múnich | 1998 | — |
| Odessa Filmworks | Ottawa | — | 1 |
| Odyssey Entertainment | Londres | — | 1 |
| Office de Radio et Télévision des Comores | Moroni | 14 de diciembre de 2015 | — |
 Office de Radiodiffusion Télévision Française | París | 1964 | 3 |
 OFFICE TO ONE | Roppongi | 5 de junio de 1963 | — |
| OffSide | Roma | — | 2 |
 Oficina de Información de Guerra de Estados Unidos | Washington D. C. | 13 de junio de 1942 | 8 |
| Oficina Federal de Cultura | Berna | — | 1 |
| OGN | Seúl | 24 de julio de 2000 | — |
| Ognon Pictures | — | — | 3 |
| Ogun State Television | Abeokuta | 1981 | 2 |
 Okko | San Petersburgo | 2011 | 1 |
| Okko Production | Praga | — | 1 |
| Oktober | Helsinki | 4 de junio de 2004 | 2 |
 Olympic | — | 1962 | 1 |
| Om Films | Santa Mónica | 2006 | — |
| Ombra Films | Barcelona | — | 3 |
| Omnia Film | Múnich | — | 1 |
 Omroep NTR | — | 2010 | 5 |
| One Cool Film Production Limited | — | 2013 | 3 |
| One Fine Day Films | Berlín | 2008 | 1 |
| One Hundred Years of Film | Hong Kong | 1999 | 14 |
| One Race Films | Studio City | 1995 | 8 |
| One's Youth | — | 2015 | — |
| Onfilm | — | 1996 | 1 |
| OP Eiga | Tokio | junio 1947 | 114 |
| Open Road Films | Los Ángeles | 2011 | 4 |
 Opus Film | Lodz | 1991 | 4 |
 Orange | Issy-les-Moulineaux | 1988 | 1 |
| Orange Studio | Issy-les-Moulineaux | 22 de octubre de 2001 | 1 |
 Orbis | — | — | 1 |
 Oriental Film | Batavia | 1940 | 1 |
| Origen P.C. | — | — | 1 |
| Origin Animation | Pekín | 14 de julio de 2010 | 1 |
| Original Productions | — | 1999 | — |
 Orion Classics | Los Ángeles | 1982 | 1 |
 Orion Pictures | Los Ángeles | 1978 | 87 |
 Orisono | Lucerna | 2020 | 1 |
| Orlando Film Festival | — | 2005 | 1 |
| Oscar Film | — | — | 18 |
| Oscilloscope | — | 2008 | 5 |
| Ostankino | Moscú, Ostankino Technical Center | 27 de diciembre de 1991 | — |
 Ostdeutscher Rundfunk Brandenburg | Babelsberg | 12 de octubre de 1991 | 2 |
| Otomatic | — | — | 1 |
| Outside Films | — | — | 1 |
| Overture Films | Beverly Hills | 2006 | 3 |
| Ovídeo TV | Barcelona | — | 3 |
| Owesen-film | — | — | 3 |
| Oxford Films | — | — | 1 |
| Oxford Scientific Films | Londres | 1968 | — |
| OXYBOT | — | diciembre 2004 | 1 |
| Oy Nordisk Film Ab | Helsinki | 30 de agosto de 1984 | 1 |
 Ópera Real de Londrés | — | 1732 | 2 |
| Õ-Fraktsioon | Tallin | 14 de mayo de 2003 | 1 |
| Ö-Filmproduktion Löprich & Schlösser | Berlín | — | 2 |