Urachal affections are rare. Their variable ways of presentation may represent a diagnostic challenge. Urachal sinuses are a rare type of these abnormalities. They are usually incidental findings and remain asymptomatic unless a complication (most commonly the infection) occurs. Infection of the urachal sinus would clinically present as purulent umbilical discharge, abdominal pain, and periumbilical mass. We report herein a case of infected urachal sinus in male adult. The diagnosis was suspected clinically and confirmed with ultrasonography and computed tomography scan. A preoperative cysto-fibroscopy showed normal aspect of the bladder and excluded sinus communication. An initial broad spectrum antibiotic therapy followed by complete excision of the sinus and fibrous tract without cuff of bladder has been therefore performed. The postoperative course was uneventful. No recurrence was observed after 18 months of followup. Histological examination did not reveal any sign of malignancy.