Objective: To report on the rare case of a vaginal malignancy occurring in uterovaginal prolapse. Case Report: A 94-year-old postmenopausal woman with underlying diabetes mellitus who had been bedridden for over ten years is presented. She also had untreated longstanding uterovaginal prolapse with unknown HPV status. The investigation showed the squamous cell carcinoma (SCC) of the vagina at the lower two-thirds of the posterior vaginal wall with evidence of metastasis to the left high external iliac and internal iliac lymph nodes. Stage III primary carcinoma of the vagina with fourth-degree uterovaginal prolapse was diagnosed according to FIGO classification. Due to the patient’s frail, elderly, and bedridden status, she was given palliative radiotherapy as a treatment. The patient passed away after the fifth course of radiotherapy. Conclusion: Vaginal cancer occurring in uterovaginal prolapse patients is exceedingly rare. The incidence of vaginal cancer is commonly seen in elderly women. The management of vaginal cancer should adhere to the same guidelines, regardless of uterovaginal prolapse and its complications.