Ruler of the World (foaled 17 March 2010) is an Irish Thoroughbred racehorse who won The Derby in 2013. He was unraced as a two-year-old. In 2013, he won a maiden race at the Curragh and the Group Three Chester Vase before winning the Derby on his third appearance. Later that year, he finished second in the Prix Niel and third in the Champion Stakes. He remained in training as a four-year-old and won the Prix Foy before being retired to stud.