OOC

OOC may refer to:


 * Out of context, logical fallacy
 * Out of character, breaking character in theatrics and roleplay
 * Original Omnibus Company, a range of scale-model Buses and Trams released by Corgi Classics
 * Old Oak Common, an area of London
 * Old Oak Common TMD, railway depot in that area
 * Old Oak Common railway station, a planned railway station in that area
 * Oman Oil Company, a national oil investment company of Oman
 * Order of Canada
 * Organ-on-a-chip

Computer science

 * Object-Oriented Code, programming paradigm