The Teen Wolf actor will make his debut as Roy Harper on the CW drama in 2013, reports TV Guide.
"We were big fans of Colton from Teen Wolf, and we are thrilled he's joining Arrow," said the series' executive producer Greg Berlanti.
Harper's history in DC Comics continuity began in 1941 as Speedy, a sidekick to Green Arrow. The sometime Justice League member has also operated under the superhero names Red Arrow and Arsenal.
Within the TV show's continuity, he is billed by the network as a "handsome, street-savvy teenager from the Glades, the harsh, poverty-stricken portion of Starling City".
The character will reportedly fall for Oliver Queen's younger sister Thea (Willa Holland).
Arrow airs on Wednesdays at 8/7c on The CW.