Aim: To evaluate the functional outcome of locking plate fixation in cases of comminuted proximal ulna fractures. Methods: The Department of Orthopaedics conducted this prospective observational research. We included 40 patients with comminuted fracture proximal ulna, including fracture olecranon and Monteggia fracture, for this research. Inclusion and exclusion criteria were used to enrol patients. The research comprised patients over the age of 19 with a comminuted proximal one-third ulna fracture that was less than one month old. During the time, 22 patients with comminuted olecranon fractures and 18 patients with Monteggia fractures were treated with locking plate fixation in our prospective research