Mixed carcinoma (squamous and glandular) of the penis is a rare neoplasm with an unknown origin and a poorly defined prognosis. The mucoepidermoid carcinoma described herein has not been previously reported to our knowledge. The present carcinoma arose from and extensively ulcerated the squamous epithelium of the glans penis, including that surrounding the urethral meatus. The neoplasm was composed of well-differentiated nonkeratinizing squamous cell carcinoma associated with large areas of carcinoma formed by cell nests that contained poorly differentiated squamous elements and large eosinophilic to pale granular cells. Mucin stains revealed approximately one quarter of the pale cells contained mucous substances. These findings are virtually identical to the mucoepidermoid type of carcinoma seen in the cervix. The 3 previously reported cases of adenosquamous carcinoma of the penis demonstrated a relatively indolent course, with only one being associated with a single inguinal lymph node metastasis. That patient was alive and well 9 years following diagnosis. Our example of mucoepidermoid carcinoma appears to demonstrate a more aggressive course than those reported previously.