Mucoepidermoid carcinoma is most frequent malignant tumor of parotid gland. However, mucoepidermoid carcinoma arising from pleomorphic adenoma has been disputed and rarely reported. 54-year-old woman with pleomorphic adenoma underwent superficial parotidectomy. And 15 years later, she diagnosed mucoepidermoid carcinoma at the same side. We report the case with a review of literature.