BACKGROUND: Proximal humeral fractures are considered the last unsolved fractures in orthopaedics. The treatment is controversial and various operative modalities have been reported in the literature. The aim of the present study was to evaluate functional outcome and complication rate after open reduction and internal fixation of displaced proximal humerus fractures by proximal humerus AO stainless steel T-plate. Twenty-five (25) patients with displaced proximal humerus fractures treated with proximal humerus T-plate between May 2005 and June 2008 were included in the study. Fractures were classified according to the Neer classification into displaced 2-part, 3-part, and 4-part fractures. Patients were followed-up for a minimum period of two years. Functional evaluation was done according to the Neer scoring system. Scores were compared with other studies in the literature using similar implant. Twenty patients had 2-part fracture, four had 3-part fracture, and one had 4-part fracture. Eighty-eight [88% (n = 22)] patients had good to excellent result, eight [8% (n = 2)] had fair, and four [4% (n = 1)] had poor result. Difference in Neer's score between 2-part and 3-part fractures was not significant. Complications encountered in this series were screw backout in 8% (n = 2), superficial infection in 12% (n = 3), and avascular necrosis in 4% (n = 1) of cases. We conclude that proximal humerus AO T- plate is a cheap and easily available implant, aspects which are particularly relevant in third world countries like India. It gives reliable fixation for 2-part and 3-part fractures. Its use in more complicated fracture patterns of 4-part fractures is not recommended.KEY WORDS: Proximal humerus fractures, proximal humerus stainless steel T-plate, unstable fracture.