Spontaneous rupture of the spleen is a rare complication of infectious mononucleosis with no clear consensus on appropriate management. Although management of traumatic splenic rupture has largely moved to nonoperative treatment, splenectomy is still frequently used in dealing with rupture of the diseased spleen. Here we report the case of a 16-year-old boy with splenic rupture secondary to laboratory-confirmed infectious mononucleosis in the absence of trauma. Nonoperative management including ICU admission, serial computed tomography scans, and activity limitation was used successfully. Our experience, along with a review of the literature, leads us to conclude that splenic preservation can be a safe alternative to splenectomy in hemodynamically stable patients with spontaneous splenic rupture. This is of particular importance in the pediatric population, which is at higher risk for postsplenectomy sepsis.