The 2021 MotoAmerica Supersport Championship season was the 7th season of the supersport class of motorcycle racing within the MotoAmerica series. entered the season as the defending champion, picking up his first MotoAmerica supersport title in . However, the 9-round season concluded with Sean Dylan Kelly picking up his first MotoAmerica supersport title. This was enough to secure Kelly a move to Moto2 for 2022.