The objective of this work was to assess the prevalence of human immunodeficiency virus-related oral lesions (HIV-ROL) in HIV-positive/acquired immunodeficiency syndrome (AIDS) patients receiving highly active antiretroviral therapy (HAART) including HIV-protease inhibitors. One hundred fifty-five (154) AIDS patients (69 intravenous drug users [IDU], 53 heterosexuals, 29 males who have sex with males, 1 transfused, and 2 of unknown contagious source) receiving HAART, were examined. We found the following prevalences: HIV-ROL 53.2%; oral candidiasis 34.4%; hairy leucoplakia 26.6%; xerostomia 15.5%; herpes simplex labialis 1.9%; HIV/periodontitis-gingivitis 0.6%. No cases of Kaposi's sarcoma were observed. The highest prevalence of HIV-ROL was found in the IDU group, and in patients with viral load more than 10,000 copies and CD4(+) cell count less than 200. Using our historical controls, this suggests that the prevalence of all oral lesions, particularly oral candidiasis, herpes simplex labiali, Kaposi's sarcoma, and periodontal disease has decreased more than 30% after the institution of HAART.