List of Famous people named O

Orenthal James Simpson, nicknamed "The Juice", is an American former football running back, broadcaster, actor, advertising spokesman, and convicted felon. Once a popular figure with the U.S. public, he is now best known for being tried for the murders of his former wife, Nicole Brown Simpson, and her friend, Ron Goldman. Simpson was acquitted of the murders in criminal court, but was later found responsible for both deaths in a civil trial.

Ottakarathevar Panneerselvam is an Indian politician serving as the 2nd and current Deputy Chief Minister of Tamil Nadu since 21 August 2017. He is the coordinator of All India Anna Dravida Munnetra Kazhagam (AIADMK). He also served three times as Chief Minister of Tamil Nadu from 22 September 2001 – 1 March 2002, 29 September 2014 – 22 May 2015 and 6 December 2016 – 15 February 2017.

Olatunde Olateju Olaolorun "O. T." Fagbenle, also referred to as O-T, is British-Nigerian actor, writer, and director. He has appeared in several films, stage, and television productions.

Ovinton J'Anthony "O. J." Mayo is an American professional basketball player for the Liaoning Flying Leopards of the Chinese Basketball Association (CBA). He played a single season of college basketball for the USC Trojans while earning first-team All-Pac-10 honors. The team forfeited all of its wins that season and Mayo lost his remaining three years of National Collegiate Athletic Association (NCAA) eligibility after it was ruled he received improper benefits. Mayo entered the 2008 NBA draft and was selected by the Minnesota Timberwolves with the third overall pick. He was later traded to the Memphis Grizzlies, with whom he played four seasons. In 2011, he tested positive for a banned steroid (DHEA) and was suspended by the NBA for 10 games. Mayo signed with the Dallas Mavericks in 2012, and then with the Milwaukee Bucks in 2013. On July 1, 2016, Mayo was dismissed from the NBA for violating the league's anti-drug program. After a two-year hiatus, he resumed his career with Atléticos de San Germán of the Baloncesto Superior Nacional (BSN) in Puerto Rico.

O'Terrius Jabari "O. J." Howard is an American football tight end for the Tampa Bay Buccaneers of the National Football League (NFL). He played college football at Alabama, and was drafted by the Buccaneers in the first round of the 2017 NFL Draft.

Olanchery Rajagopal is an Indian politician, former Union Minister of State,Former Chief Minister of Kerala candidate of BJP and the MLA from Nemom and the first ever Bharatiya Janata Party member in the Legislative Assembly of Kerala. One of the major leaders of the Bharatiya Janata Party from Kerala, he has held various ministerial portfolios including Defence, Parliamentary Affairs, Urban Development, Law, Justice, Company Affairs, and Railways. Rajagopal was a two-time MP in Rajya Sabha, the upper house of Indian Parliament from 1992 till 2004. Rajagopal was also a member of Kerala state government's legistative assembly subject committee on Petitions & Committee of Public Work, Transport and Communications.

Jaisha Orchatteri Puthiya Veetil, commonly known as O. P. Jaisha, is an Indian track and field athlete from Kerala. She is the current national record holder in the marathon, a distinction she achieved by clocking 2:34:43 at the 2015 World Championships in Beijing. In the process she bettered her own mark of 2:37:29, set at the 2015 Mumbai Marathon. She is also a former national record holder in the 3000 metres steeplechase.

O Sonfa, commonly known as her Korean name Oh Seon-hwa, is a professor in the School of International Relations at Takushoku University in Tokyo, she is also active as an author and journalist in Japan. She is a critic in many fields such as current issues, history, and culture, particularly in East Asian Countries. Originally from Jeju-do, South Korea, she left for Japan in 1983 and received a BA degree from Daito Bunka University and an MA degree from the Graduate School of North American Studies at Tokyo University of Foreign Studies. She went on to naturalise as a Japanese citizen.