It is frequently difficult to assess the presence of malignancy in patients with parotid tumor, because of unreliable diagnostic tools and riskful preoperative biopsy, In our case, a parotid adenocarcinoma and pleomorphic adenoma was revealed on permanent histologic section, which was made a impression as pleomorphic adenoma on preoperative Tru-Cut biopsy and intraoperative frozen section, So, the most accurate diagnosis of the parotid malignancy is a complete removal of tumor tissue, accompanied with permanent histologic section.