Synovial chondromatosis is a benign lesion forming multiple round cartilagenous nodules or osseous loose bodies in joint cavity. Predilection sites are known as knee, hip and elbow joints. However, the involvement of ankle joint was rarely reported in the literature. Moreover, extraarticular chondromatosis in synovial sheath or bursa of extremities is extremely rare. We present a case of synovial chondromatosis of the left ankle joint and flexor hallucis longus tendon sheath.