Boldbaataryn Bütekh-Üils (; born February 10, 1990 in Ulaanbaatar) is a Mongolian swimmer, who specialized in breaststroke events. Boldbaatar represented Mongolia at the 2008 Summer Olympics in Beijing, and competed for the men's 100 m breaststroke event. He swam in the second heat of the competition, finishing in sixth place, with a time of 1:10.80. Boldbaatar, however, failed to advance into the semi-finals, as he placed sixtieth in the overall rankings.