Ovarian squamous cell carcinoma is a rare and aggressive ovarian neoplasm, where most of the cases arise from mature teratoma, which represents up to 20% of all ovarian tumors. Moreover, primary squamous cell carcinoma is considered to be related to human papillomavirus infection. The diagnosis is difficult and metastasis from bladder, genital tract, lung, and digestive tract cancers must be ruled out. There are no guidelines for treatment, however, radical surgery combined with adjuvant chemotherapy and radiation therapy, are the most common approach. We present the case of a young women diagnosed with a de novo ovarian squamous cell carcinoma, as well as the treatment and follow-up that she received.