IntroductionInguinal herniation of the ureter is a rare entity that occurs either as a complication of renal transplantation or spontaneously. Patients may suffer from obstructive uropathy or groin pain due to the unusual ectopic course of the ureter. This case report highlights the importance of recognizing a ureteroinguinal hernia.MethodsIn this case report, we present a 75-year-old man with a surgical history of a right inguinal hernia repair who was referred to our center with burning left inguinal pain that persisted for two weeks. The patient's history and physical examination were consistent with an inguinal hernia. The suspected indirect inguinal hernia was found on preoperative imaging to be a tubular structure distinct from the intestine or adjacent organs. An open exploration of the inguinal canal was performed to prevent further hernia development.ResultsThe unusual structure in the inguinal canal turned out to be an ectopic ureter originating from the left upper pole moiety of the left duplex kidney (i.e., with duplicated ureters) and containing concentrated urine, as confirmed on a postoperative computerized tomography urogram.ConclusionIt is crucial to perform a thorough clinical examination and utilize adequate imaging modalities before surgical procedures when encountering unidentified structures.