Although the most common gynecologic tumor of the female genital system is endometrial adenocarcinoma, endometrial squamous cell carcinoma (ESCC) is rarely seen. The presence of ESCC is commonly known as a concomitant tumor secondary to cervical squamous cell carcinoma (SCC). However primary endometrial squamous cell carcinoma (PESCC) is a more rare tumor type. In situ carcinoma, defined as the inflammation of entire intraepithelial tissue with dysplastic cells without identifying any concomitant invasion or metastasis, is considered to be among the precancerous lesions of the female genital system. In situ squamous cell carcinoma cases, especially identified in the cervical region, can be rarely observed in the endometrial tissue. In this case report, the authors aimed to discuss a case of cervical and ESCC in situ which is reported for the first time in the literature.