METHODS This case report presents a patient with ureter injury after anterior spinal fusion and its management. OBJECTIVE To present possible causes, symptoms, diagnostic approach, and management of this rare complication. BACKGROUND The reported complications of anterior surgical approaches to the lumber spine have been predominantly vascular or neurologic. The susceptibility of the ureter to injury is emphasized by the description of an as-yet-unreported case of ureter laceration after anterior lumbar fusion. METHODS Ureter injury was diagnosed using computed axial tomography, ultrasonography-guided aspiration, and chemical analysis of the aspirate after anterior spinal fusion. RESULTS Early diagnosis of this injury prompted a ureter stent placement and prevented additional deterioration of renal function and infection. CONCLUSIONS The ureter is prone to injury if not identified and protected when sharp and pointed instruments are used for retraction. Abdominal mass, low-grade fever, and leukocytosis should prompt use of computed tomography or ultrasonography-guided aspiration.