A case of Splenic Spontaneous Rupture (SSR) due to Infectious Mononucleosis is presented, occurring after a slight clinical course without significative abdominal pain. The SSR was recognized by ultrasonography and CT, with free intraperitoneal liquid. The evolution was successful with non operative management. The Medical literature concerning SSR is comment, enhancing the possibility of non operative management of SSR associated to infectious mononucleosis.