Complete suprapatellar plica is a rare congenital anomaly that separates the suprapatellar bursa from the knee joint cavity. Although the pathological incidence of this condition is not known, it can cause patellofemoral symptoms, anterior knee pain, and rarely hemarthrosis. We report a patient with a hematoma in an unusual location just three weeks after an arthroscopic procedure, associated with a complete suprapatellar plica undetected during primary surgery. The hematoma was not in the synovial cavity, rather between the quadriceps tendon and the synovial membrane and presenting with pain and catching. This unusual location has not been reported before. Repeat arthroscopic surgery with drainage of hematoma and plica resection relieved the symptoms.