Spontaneous splenic rupture is a rare cause of peritoneal bleeding. Etiology is usually infections (viral, bacterial or parasitic) and blood diseases (leukemia, lymphoma, dysglobulinemia). We report the first case of spontaneous splenic rupture secondary to hilar Kaposi's sarcoma in an HIV positive patient. Emergency splenectomy was performed to achieve hemostasis, and the etiological diagnosis of this spontaneous splenic rupture was based on the histological analysis.