Hemophagocytic syndrome (HPS) sometimes occurres in patients with acquired immunodeficiency syndrome (AIDS). Human herpesvirus-8 (HHV-8)/Kaposi's sarcoma (KS)-associated herpesvirus has so far been recognized as a trigger of HPS in immunosuppressed subject. We describe a 39-year-old man with AIDS who had widespread mucocutaneous and pulmonary KS and severe HPS. No opportunistic infections or neoplasias were detected except for KS. HHV-8-DNA could be detected in this patient by polymerase chain reaction (PCR) in the serum. Clinical symptoms and cytopenia originating from HPS were reduced by pulse therapy of corticosteroid, antibiotics, and virucides, but recurred with dose reduction of the steroid. Mucocutaneous tumors, edema, and dyspnea had progressed rapidly at this time. Liposomal doxorubicin was given and showed marked effects on both mucocutaneous and plural tumors. HPS also subsided and the serum HHV-8 DNA level markedly decreased after initial treatment with liposomal doxorubicin. HHV-8 clearance with liposomal doxorubicin has recently been reported. Liposomal doxorubicin suppressed not only the widespread KS tumors, but also HHV-8 viremia resulting in decreased HPS in this patient.