Kateryna Lahno (b. December 27, 1989) is a Ukrainian chess player. She earned the FIDE title of Woman Grandmaster at the age of 12 years and 4 months, breaking Judit Polgar's record to become the youngest ever to earn this title. On the April 2005 list, Lahno's FIDE Rating was 2467, 20th best among female chess players. As of April 2004, she had one of three norms necessary to earn the Grandmaster title.
Lahno was the fifth seed for the 64-player knockout 2004 Women's World Championship. Although Lahno, unlike Polgar, competes for the women's title, both have stated that their true goal is to be simply World Champion.