Introduction: Despite the availability of numerous treatment options, managing unstable proximal humeral fractures remains a significant surgical challenge. Utilizing a PHILOS plate is an effective surgical technique for addressing these fractures. This approach provides stability and support to the fracture site, promoting proper healing and potentially improving patient outcomes. Aim of the study: The aim of this study was to assess the functional outcome of PHILOS plate fixation in proximal humerus fractures. Methods: This prospective study was conducted in the the Department of Orthopedic Surgery, National Institute of Traumatology and Orthopedic Rehabilitation (NITOR), Sher-e-Bangla Nagar, Dhaka, Bangladesh during the period from January 2009 to December 2010. A total of 80 patients aged over 18 years were included in the study. Patients with open, pathological and ipsilateral distal fractures in the same limb were excluded from the study. Result: The youngest and the oldest one were 23 and 78 years respectively. Majority of the patients were male and business was their main occupation. Fifty patients (62.5%) presented with 3-part fractures, ten (12.5%) with four-part fractures and twenty (25%) with fracture dislocation. The interval between injury and plate fixation was 18 days and minimum and maximum interval was 2 and 78 days respectively. Majority (92.5%) of the injury was caused by high-velocity accident. Evaluation of the outcome at 6 months showed that 62.5 percent of patients had good outcome, 25 percent patients had fair outcome. Conclusion: PHILOS plate fixation for proximal humeral fractures provides stable fixation and good functional outcomes, particularly in elderly patients.