The differential diagnoses for anterior wall vaginal prolapse (AWVP) include cystocele, enterocele, urethral diverticulum, and Gartner duct cyst. We present a case of a patient with a known solitary right kidney (congenital absence of a left kidney) presenting with lower urinary tract symptoms, absence of urinary incontinence, and feeling of bulge in the vagina. Physical examination revealed grade II AWVP. Because congenital solitary kidney can be associated with other possible genitourinary abnormalities, a pelvic magnetic resonance imaging was obtained. Magnetic resonance imaging demonstrated a tubular structure spanning the left retroperitoneum to the region of the AWVP. Urodynamics revealed an obstructive voiding pattern during pressure-flow phase. The combination of transvaginal and transabdominal surgical excision of the tubular structure resolved the patient’s lower urinary tract and prolapse symptoms. Anatomically, her AWVP was corrected. Histopathologic examination of the tubular structure revealed presence of urothelium lining the lumen of the tubular structure consistent with a ureter. This case represents the rare situation in which an ectopic ureter presented as an AWVP. However, patients with congenital solitary kidney presenting with vaginal prolapse should raise the suspicion for other associated genitourinary anomalies, whether these anomalies are related to the prolapse or not. Cross-sectional imaging should be performed in these situations to delineate precise anatomy.