Septic thrombophlebitis of the portal vein (STPV) is an extremely rare but potentially fatal complication of acute appendicitis. Patients often present with fever and abdominal pain. In patients presenting with these symptoms, deterioration in liver function tests and right upper quadrant pain should be taken into consideration when evaluating thrombophlebitis. It is thought that the infective process originating from the areas drained by the portal vein plays a role in the etiology of STPV. In this case, we aimed to present the imaging findings of STPV, a rare complication of perforated appendicitis, and to raise awareness of the diagnostic approach