A child with shoulder pain and great palpable mass without any injury history is an emergent case until the diagnosis is confirmed. We report the clinical findings, imaging features, surgery and histological analyses of primary synovial chondromatosis in glenohumeral joint, biceps tendon sheath and subcoracoid bursa in a child, aged 14. Primary synovial chondromatosis is characterised by multiple calcified nodules in joints, tendons or bursa areas. The condition is more usual in large joints, in particular in lower extremities. It may be symptomless until the volume of chondromatosis has increased to such an extent that it results in pain, locking symptom or palpable mass. The treatment is removal of the loose bodies and potentially synovectomy, in means of open or arthroscope-assisted surgery. Postoperative follow-up is recommended due to the risk of recidivism and potential malignant transformation. The disease is more common in older patients and there are only isolated cases in pediatric population.