Karina Smirnoff is a Soviet-born American professional ballroom dancer of Ukrainian origins. She is known as a professional dancer on Dancing with the Stars, where she won the thirteenth season with army veteran and soap opera star J. R. Martinez. She has also won two runner-up titles, a semifinal title, and several quarterfinal titles.

Season four of Dancing with the Stars premiered on March 19, 2007, on the ABC network.