Malignant mullerian mixed tumors (MMMTs) of the uterine cervix are rare; less than 30 cases have been reported in the literature and only 14 have been described in detail. As a result, the clinical and pathologic features of these tumors are not well characterized. The clinicopathologic features of nine cervical MMMTs (all cases referred because of problems in differential diagnosis) are reported here and the literature on the previously described cases is reviewed. The patients ranged in age from 23 to 87 (mean 65) years. The initial manifestations were mainly vaginal bleeding or spotting or, less commonly, an abnormal Pap smear. All of the patients had a cervical mass on examination. Of the eight patients for whom staging information was available, seven were stage Ib and one was stage II. Treatment in six patients was hysterectomy with lymphadenectomy in five; postoperative radiation therapy, chemotherapy, or both were given to two of these patients. The remaining three patients were treated by local excision (with lymphadenectomy in one) followed by radiation therapy, chemotherapy, or both in two. Follow-up, available for seven patients, revealed recurrent pelvic tumor in two patients at 1.6 and 3.0 years, respectively; the former patient died from tumor at 3.5 years whereas the latter was alive with tumor at 4.5 years. Another patient was well for II years but died 13 years postoperatively from colonic adenocarcinoma. Four other patients were alive with no evidence of tumor at postoperative intervals of less than 2 years. Gross examination revealed polypoid or pedunculated masses 1.1 to 10.0 cm in maximal dimension that invaded the cervical wall in 50% of the hysterectomy specimens. On microscopic examination, three tumors contained a predominant or exclusive epithelial component of basaloid carcinoma, two contained squamous cell carcinoma, and four contained adenocarcinoma (endometrioid in three and nonspecific in one). In seven tumors, the sarcomatous component was homologous, usually resembling fibrosarcoma or endometrial stromal sarcoma; in four of these tumors, myxoid change was prominent. Two tumors contained heterologous sarcomatous elements. In three patients, a pure carcinoma abutted the MMMT: an adenoid basal carcinoma in two (with a minor component of in situ and invasive squamous cell carcinoma in each) and an endometrioid endocervical adenocarcinoma in one. These findings, combined with analysis of the previously reported cases, indicate that cervical MMMTs, compared to their counterparts in the corpus, are more commonly confined to the uterus at presentation, may have a better prognosis, and frequently have a nonglandular epithelial component.