Objective To evaluate the masticatory efficiency after mandibular angle ostectomy. Methods Fifteen patients who accepted mandibular angle ostectomy (bilateral jaw edge of the mandibular angle resection and mandibular body outer panel split) were selected. Periodontal disease, temporomandibular joint pain and partial jaw were screened. The masticatory efficiency of the patients were evaluated by means of sieving and weighing almond and jujube before operation, 1 month and 6 months after operation. Results There were significant differences between the average masticatory efficiency 1 month after operation and before operation (P0.05). Conclusion Mandibular angle ostectomy has no effect on the masticatory efficiency.