Sevastyanova competed as an individual gymnast on the junior level, appearing in international competitions. She competed in Miss Valentine 2005 in Estonia with Margarita Mamun. Later, she started competing with the Russian Group.
Sevastyanova was a member of the Russian Junior Group that won the gold medal at the 2010 Youth Olympic Games. In 2012, she was selected to compete with the Russian Senior Group as a replacement for the injured Natalia Pichuzhkina. They won the gold medal at the 2012 European Championships and at the World Cup Final in Minsk.