The actor appeared at the beginning of the current season as Dr Andrew Perkins, a counsellor who was drafted in to help the group come to terms with the shootings.
According to Entertainment Weekly, Tupper will reprise his role in a multi-episode arc this spring.
Details of his storyline have not yet been revealed, but during his first appearance he had a romance with Teddy (Kim Raver).
Tupper has previously starred in shows including Men In Trees and Mercy.
Grey's Anatomy airs on Thursdays at 9/8c on ABC in the US and on Wednesdays at 10pm on Sky Living in the UK.