A 14-year-old girl presented with pain during the motion of knee joint. Multiple loose bodies were detected in proximal tibiofibular joint area in simple radiography. MRI demonstrated multiple small calcifications in the cystic lesion which was located around the popliteus muscle from the proximal area of fibular head to the tibial attachment area of popliteus muscle. Loose bodies were excised successfully with only arthroscopic approach through popliteal hiatus. To our knowledge, arthroscopic excision of synovial chondromatosis of the proximal tibiofibular joint has not been reported.