Müllerian adenosarcoma (MS) is a rare neoplasm of uterine cervix composed of benign epithelial and malignant stromal components. An aggressive variant of adenosarcoma, müllerian adenosarcoma with sarcomatous overgrowth (MASO) is extremely rare. The difference between MS and MASO is the pure high grade sarcoma features in MASO. In this report we present a MASO case, derived from uterine cervix of a 60 year-old-female patient presenting as a cervical polypoid mass, to our knowledge the second case of the English literature. In spite of sarcomatous overgrowth, high mitotic activity and huge tumor size of 12,5 cms, it displayed no myometrial invasion, vascular invasion and heterologous elements. The patient has been clinically free of disease for 14 months of follow up after total abdominal hysterectomy and bilateralsalpingo-oopherectomy. The difficulties in diagnosis and treatment of this entity will be evaluated in this report.