Rationale:Concomitant malignancy of the endometrium and cervix is extremely rare.Patient concerns:A 56-year-old female presented to the Women's Hospital, School of Medicine, Zhejiang University, complaining of irregular vaginal bleeding. The human papillomavirus test (type 18/45) was positive. We performed dilation and curettage; pathology revealed moderately differentiated endometrial carcinoma exhibiting squamous differentiation. The epithelium of the cervical uterus was atypical upon biopsy.Diagnoses:Histological and immunochemical tests confirmed a diagnosis of endometrial carcinoma concomitant with cervical adenocarcinoma.Interventions:She underwent laparoscopic staging surgery.Outcomes:The patient fully recovered with only surgery.Lessons:Endometrial carcinoma concomitant with cervical adenocarcinoma is very rare. It is imperative to schedule adequate examination, and to perform careful preoperative diagnosis and appropriate treatment to minimize relapse.