Abstract: Observations on histology and immunohistochemistry of 16 vesicular nucleuscell carcinomas and 19 undiferentoated carcinomas in nasopharynx showed that although the histological picture of vesicular nucleus cell carcinoma differed from theone of undifferentiated carcinoms,but there were no significant differences in expressions of different molecular weight cytokeratins between the former and the latter.We believed that vesicular nucleus cell carcinoma was a form of undifferentiatdcarcinoma in the histogenesis, it should be incorporated into undifferentiated type ofnasopharyngeal carcinoma