Sonja Johnson (born 14 December 1967 in Albany, Western Australia) is an Australian equestrian who won a silver medal at the 2008 Summer Olympics in Beijing as part of the three-day eventing team.
She grew up on a farm and says she began riding at the age of three to help muster cattle on the property.
In 2006, she won the Melbourne 3-Day-Event on the horse Ringwould Jaguar.