Background. Kaposi’s sarcoma (KS) is the most frequent neoplasm inpatients with acquired immunodeficiency syndrome (AIDS). Although many studies on KS epidemiology have been performed in other countries, few have been carried out in Brazil despite the high incidence of AIDS. Methods. One hundred and seven KS patients seen in S.ao Paulo, Brazil, between August 1995 and November 1998 were studied. The patients were followed for 1 year with assessment of the immunologic status, improvement of the lesions, treatment, and causes of death at the end of this period. Results. KS occurred mainly in men (94.4%) with a mean age of 37 years, and 25.2%of these patients were found to be human immunodeficiency virus (HIV) seropositive throughKS. HIV was acquiredmainly through homosexual contact. The patients presented an average of 15.9 KS lesions at the first visit and the mean duration of KS lesions before the first visit was 15.5 months. The clinical presentation was predominantly papules and plaques, and 33.6%presented with mucosal and/or visceral disease. KS affected mainly the lower limbs. The mean time since the diagnosis of HIV infection was 42.4 months. The CD4+cell count was lower than 200 cell/mm3 in 60.8%of patients, but patients with a complete response showed an improvement in immune status after 1 year. Patients who did not show progression received a protease inhibitor as part of highly active antiretroviral therapy (HAART). Patients treated exclusively with HAART presented a complete response (61.6%), partial response (23%) or progression (15.4%) of KS. Conclusions. An improvement in immune status and the use of HAART were the most important prognostic features. Background. Kaposi’s sarcoma (KS) is the most frequent neoplasm inpatients with acquired immunodeficiency syndrome (AIDS). Although many studies on KS epidemiology have been performed in other countries, few have been carried out in Brazil despite the high incidence of AIDS. Methods. One hundred and seven KS patients seen in S.ao Paulo, Brazil, between August 1995 and November 1998 were studied. The patients were followed for 1 year with assessment of the immunologic status, improvement of the lesions, treatment, and causes of death at The end of this period. Results. KS occurred mainly in men (94.4%) with a mean age of 37 years, and 25.2% of these patients were found to be human immunodeficiency virus (HIV) seropositive through KS. HIV was acquired mainly through homosexual contact . The patients presented an average of 15.9 KS lesions at the first visit and the mean duration of KS lesions before the first visit was 15.5 months. The clinical presentation was predominantly papules and plaq ues, and 33.6% presented with mucosal and / or visceral disease. KS affected mainly the lower limbs. The mean time since the diagnosis of HIV infection was 42.4 months. The CD4 + cell count was lower than 200 cells / mm3 in 60.8% of patients, but patients with a complete response showed an improvement in immune status after 1 year. Patients who did not show progression received a protease inhibitor as part of highly active antiretroviral therapy (HAART). Patients treated exclusively with HAART presented a complete response (61.6 % improvement, partial response (23%) or progression (15.4%) of KS. Conclusions. An improvement in immune status and the use of HAART were the most important prognostic features.