Kaposi's sarcoma is a rare manifestation in children with human immunodeficiency virus (HIV) infection. It is mostly reported in children living in African countries. We describe a Taiwanese child who initially presented with fever of unknown origin and multiple hepatosplenic masses and in whom, after further investigations, the diagnosis turned to be an HIV infection with hepatosplenic Kaposi's sarcoma. She underwent splenectomy and received highly active anti-retroviral therapy with good clinical, virological and immunological responses.