We report herein the case of a 26-year-old man who suffered a spontaneous splenic rupture during the course of a rubella infection. Initially, he presented with a high fever accompanied by a skin rash extending from the body trunk to the extremities and was admitted to hospital 3 days after onset for sudden upper abdominal pain radiating to both shoulders. On admission, he was pale and sweating with hypotension. An abdominal ultrasonographic study revealed a collection of fluid in the perisplenic space and exploratory laparotomy confirmed an intraabdominal hemorrhage from a ruptured spleen. The patient was treated by splenectomy and recovered uneventfully. The excised spleen was found to be moderately enlarged with a denuded capsule. Because the patient had no history of any external trauma and a positive serological test for rubella, we concluded that rubella contributed to the spontaneous splenic rupture in this case.