This retrospective study concerns benign parotid gland tumors in 306 Japanese patients who were treated by partial parotidectomy with preservation of the facial nerve. There were no recurrences in 112 with a pleomorphic adenoma in over a 5-year follow-up. Facial weakness and temporal paresis occurred in 18% of 232 patients and Frey's syndrome in 18% of 93 with longer than a 3-year follow-up. In comparison with reported results of lateral or superficial parotidectomy, partial parotidectomy with preservation of the facial nerve seems preferable for treatment of patients with a benign parotid gland tumor.