PURPOSE: To evaluate the mechanism of the humeral fractures induced by arm wrestling and the clinical results of its treatment. MATERIALS AND METHOD: We reviewed 7 humeral fractures induced by arm wrestling; 3 humeral shaft fractures, 4 humeral medial epicondyle fractures. The mechanism of the fractures and the clinical results were assessed by history and radiographs. RESULTS: Shaft fractures were produced by twist and axial compression force. Humeral medial epicondyle fractures were the avulsion fractures by excessive contraction of flexor muscles and developed in young age. We operated 6 of them and in all cases, we could obtain fracture healings without complication. CONCLUSION: The humeral fractures induced by arm wrestling have the differences in the ages and mechanisms as to the locations of the fractures and if the proper treatment is performed, the clinical results are satisfactory.