After attending MacRobertson Girls' High School in Melbourne, McEwan started acting, appearing in several television series including Ocean Girl and Funky Squad. In 1991 she was nominated for a Gladys Moncrieff Award for "Outstanding New Talent" by the Music Theatre Guild of Victoria after her performance in Annie. McEwan has also appeared several times in the soap opera Neighbours. Her first role as Sonia came in 1989, then in 1991 she played Sarah Livingston, this was followed by Nicole Cahill in 1995. She played Penny Watts in 2002.