Coracoclavicular joint (CCJ), occasionally presents between the conoid tubercle of the clavicle and the superior surface of the horizontal part of the coracoid process, is a diarthrodial synovial joint with bilateral or unilateral articular facet. By anatomic studies, osteological studies and radiological surveys, it has been confirmed that CCJ is influenced by both genetic and environmental factors. It could not affect the shape of the scapula and clavicle, but could lead to degenerative changes of the acromioclavicular joint and acromioclavicular joint. CCJ plays a crucial role in assisting upward rotation of the clavicle in arm elevation. The overall prevalence of CCJ in humans ranges 0.04％ - 30％. Its occurrence rate obtained from radiological studies is generally lower than skeletal or cadaveric studies. Gender difference is not statistically significant. Right side is more common than the left. There are ethnic and geographic differences in the incidence of CCJ. The frequency in East Asia, especially southern China, is higher than others. It decreases as the distance from the epicentre in China increases. CCJ is rarely symptomatic, and the most common symptom is shoulder pain. Other symptoms include limitation of arm movements, radiating pain of the upper limb, paralysis of the hand. The etiologies may be the compression of the brachial plexus, the collision between the clavicle and coracoid process and the degenerative changes of the sternoclavicular and acromioclavicular joints. Differential diagnosis could be made by local anaesthetic injection under image guidance. Conservative treatment, such as anti-inflammatories, physiotherapy, lifestyle modification, local corticosteroid injection under fluoroscopy should always be the first-line treatment. Surgery could be performed if conservative treatment fails.