Twenty-five cases of mucoepidermoid carcinoma of the salivary glands were studied with respect to clinico-pathologic features, prognostic factors, and c-erbB-2 oncoprotein expression. Fourteen cases were located in parotid glands, 2 in submandibular glands and 9 in minor salivary glands. Fourteen patients were confirmed to have local recurrences, 6 patients manifested systemic metastases, and 10 patients died of the disease. They were histologically graded as I in 5, II in 12 and III in 8 cases respectively, and the histologic grade was significantly correlated with disease-free interval and overall survival of the patients. c-erbB-2 overexpression was observed in 9 cases (36%), with a trend to be associated with the higher grade, but was not evaluated as a significant survival-related factor in this series. Larger size and major gland location of the tumors were correlated with more frequent regional lymph node metastases. The present study showed that c-erbB-2 overexpression was not uncommonly present in mucoepidermoid carcinoma of the salivary glands, especially of higher grade, and the histologic grade was the most important and handy prognostic indicator.