Asociația Club Sportiv Sepsi OSK Sfântu Gheorghe, commonly known as Sepsi OSK is a Romanian professional football club based in Sfântu Gheorghe, Covasna County, that competes in the Liga I. Founded in 2011, it achieved promotion to the top tier in six years by quickly climbing through the Romanian league system. Sepsi thus became the first team from Covasna—a county with a majority of Székely ethnics—to play in the Liga I. It also qualified for two Cupa României finals, in the 2019–20 and 2021–22 seasons. Sepsi's club colours are red and white in honour of the local football tradition.