Synovial plicae, both symptomatic and asymptomatic, are increasingly being diagnosed with the expansion of arthroscopic procedures in synovial joints. Ankle plicae, however, remain an uncommon diagnosis and have previously only been reported as symptomatic in the post-traumatic ankle. Here the authors present a case report of an atraumatic, symptomatic ankle plica successfully treated with arthroscopic debridement. © 2012 American College of Foot and Ankle Surgeons.