The daughter of two former Soviet champion gymnasts and Olympic gold medalist Valeri Liukin, Liukin was the 2008 Olympic individual all-around gold medalist, the 2005 and 2007 World Champion on the balance beam, and the 2005 World Champion on the uneven bars. With nine World Championships medals, seven of them individual, Liukin tied with Shannon Miller as the American gymnast having won the most World Championship medals. Liukin has also tied Miller's and Mary Lou Retton's records as the American gymnast having won the most medals in a single Olympic Games.

Liukin has served as a Longines Sports Ambassador of Elegance.. In June 2008, Liukin and her teammates Shawn Johnson and Alicia Sacramone became the first female athletes ever to be signed as CoverGirl spokesmodels. She has also helped with World Vision, to help her home state of Texas to recover from Hurricane Ike.