In April 2016 McKeon was selected as part of the Australian team for the 2016 Summer Olympics held in Rio de Janeiro, Brazil. Her brother David was also selected meaning the pair were the first brother and sister to swim at an Olympic Games for Australia since John and Ilsa Konrads in 1960. At the 2016 Summer Olympics she led off the 4 × 100 metre freestyle relay that won a gold medal in a world record time of 3:30.65. McKeon also went on to win a pair of silvers as a part of the 4 × 200 metre freestyle and 4 × 100 metre medley relays. She was one of five Australian individual medallists in swimming in Rio, having won a bronze medal in the 200 metre freestyle with a time of 1:54.92. In the 100 metre butterfly, she finished 6th.