Oksana Omelianchik (Ukrainian: ????´?? O?????´???i??? ??????´????; alternative transliterations: Oksana Omiel'jantchik, Oksana Omeliantchik, Oksana Omelyanchyk; born 2 January 1970) is a retired Soviet gymnast and the all-around gold medalist of the 1985 World Championships.
Omelianchik was most known for her enthusiastic showmanship, difficulty and originality, including pioneering back-to-back tumbling.