Cogan's syndrome (CS) is a rare multisystemic disorder characterized by inflammatory eye diseases and vestibuloauditory dysfunctions. It is prone to be misdiagnosed or overlooked, and the prognosis of those delayed-diagnosed CS is not optimistic. Despite isolated patient responses to systemic treatment including steroids and methotrexate, there is currently no general consensus on an effective treatment for CS. We present a case of Cogan's syndrome remission associated with leflunomide (LEF) in a juvenile patient. To date, there is no such report on CS, especially in children, which is successfully treated by LEF in combination with glucocorticoids.