The shoulder is especially susceptible to stiffness following injury because of the formation of adhesions. Early mobilization prior to maturation of adhesions around the joint gliding surface is, therefore, an essential step in the management of the proximal humerus comminuted fractures. Our aims were accurate reduction and stable fixation to allow early mobilization and to achieve full functional recovery. During the eight-year period from January 1986 to June 1994, 51 cases patients were treated surgically for comminuted fractures of the proximal part of the humerus by T-plate at our hospital. The results were summarized as follows; 1. There were 17 cases of the two-part fractures, 31 cases of the three-part fractures and 3 cases of the four-part fractures following to Neer's classification. 2. The most common cause of injury was road traffic accident (34 cases). 3. The excellent or satisfactory results were seen E2% of the two-part fractures and 81'Fo of the three-part fractures, whereas 67% of the four-part fractures. 4. The most frequent complication of comminuted fractures were motion limitation and pain(5 cases), delayed union(2 cases), plate bending(1 case) and infection(1 case) but avascular necrosis of the humeral head, non-union, myositis ossificans and plate breakage had not been developed in these cases. 5. T-plate was one of the good internal fixation devices for surgical treatment of the comminuted fractures of the proximal humerus.