OIC or Organisation of Islamic Cooperation is an international organisation of Muslim nations.
OIC may also refer to:
- Offer in compromise, an agreement to reduce debt to the United States Internal Revenue Service
- Officer in Charge (Philippines), the specific status of a temporary head of a local government or agency in the Philippines
- Officer in charge (police), a gazetted officer in command of a police station in Sri Lanka
- Officer in Command, primarily used in the United States Uniformed Services as well as police and sheriff's departments
- Two incarnations of the Oklahoma Intercollegiate Conference: Oklahoma Intercollegiate Conference (1914–1928), Oklahoma Intercollegiate Conference (1974–1997)
- Opportunities Industrialization Center, a nonprofit adult education and job training organisation headquartered in Philadelphia, Pennsylvania, United States.
- Open Interconnect Consortium
- Opioid-induced constipation
- Order of the Imitation of Christ, a monastic order in the Syro-Malankara Catholic Church
- Orkney Islands Council, the local government authority for Orkney, Scotland, United Kingdom
- OIC, the IATA code for Lt. Warren Eaton Airport in Norwich, New York, United States
- Octahydroindole-2-carboxylic Acid (Oic)
- Office of the Independent Counsel, an office of the U.S. Department of Justice
- Outline in Color, a rock band from Tulsa, Oklahoma, United States