Synovial chondromatosis is the chondroid metaplasia of the synovial membrane, Large joints such as the knee and hip are commonly involved. Synovial chondromatosis very rarely develops within the shoulder joints. We have experienced the synovial chondromatosis developed in the right subscapular recess communicating the shoulder joint of a 30 year-old-female who was diagnosed by plain radiograph, MRI and microscopic findings, and then treated by arthroscopic synovectomy and removal of loose bodies.