Karen Grasso (born August 9, 1993) is a pioneering Mexican mixed martial artist who made history as the first Mexican female fighter to win a UFC championship, holding the title of former UFC Women's Flyweight Champion. She began her professional career in 2012 with an undefeated 5-0 start, later competing in Invicta FC—where she earned a Fight of the Night bonus—before signing with the UFC in 2016. Her early UFC tenure was marked by challenges, including a loss to Felice Herrig and a significant weight-cutting mishap in 2020 that forced her to move up permanently to flyweight. This division change proved pivotal, as she climbed to the top of the rankings and captured the championship. As of early 2026, she is ranked #3 in the UFC women's flyweight division and #7 pound-for-pound, while also serving as a UFC analyst for Spanish broadcasts.