John M. Oxx (born 14 July 1950) is a retired Irish trainer of thoroughbred racehorses. By the end of the 2009 season Oxx had trained 35 Group One winners over his career, including the winners of 11 Classic races. He is best known as the trainer of Sinndar and Sea The Stars. Oxx has been widely praised for the care and undemonstrative authority with which he approaches the training and racing of his horses. He is particularly known for being highly selective when choosing when and where his horses will run.