Olusegun Mimiko (Yoruba: Olúṣẹ́gun Mímikò; born 3 October 1954) is the current governor of Ondo State, Nigeria.
Dr. Olusegun Mimiko competed in gubernatorial elections on April 14, 2007, against the incumbent Olusegun Agagu and lost the contest in April 2007 according to the result released by the Independent Electoral Commission INEC. Mimiko contested this decision at the election tribunal and Agagu lost office on February 23, 2009 following an AppealCourt ruling which cited irregularities in the 2007 election, and was replaced by Mimiko as governor. Mimiko is currently the first and only member of the Labour Party to win gubernatorial office in Nigeria.
Governor Olusegun Mimiko was said to have won the election on October 20, 2012 enabling him to continue in office for a second term making him the first Governor in Ondo State to win a second term election.Mimiko's victory is now being contested by the candidate of the ACN - Rotimi Akeredolu, the candidate of the PDP - Olusola Oke and the candidate of the CPC - Olusoji Ehinlanwo
In October 2012, Mimiko stood as the Labour Party candidate for Nigeria’s Ondo State and polled the highest votes in the elections. The Ondo State governor, Olusegun Mimiko on Thursday October 2, 2014 officially decamped to the Peoples Democratic Party (PDP) from the Labour Party. He and his supporters were received back to the fold by the Vice President, Namadi Sambo, Senate President, David Mark, Deputy National Chairman, Uche Secondus and top party men at the Banquet Hall of the State House, Abuja.
 On October 2nd he officially left the labour party for peoples democratic party