The aim of this work is to analyze if the highly active antiretroviral therapy (HAART) has any effect in the number of peripheral monocytes expressing the tolerogenic molecule human leukocyte antigen G (HLA-G) in HIV-1 infected individuals. In this sense, expression of HLA-G was measured by flow cytometry on peripheral monocytes from HIV-1 antiretroviral-receiving and antiretroviral naïve patients and in HIV-1 patients at different times after the antiretroviral treatments were removed. It was found an increment of monocytes expressing HLA-G in HIV-1 infected individuals receiving HAART, whereas monocytes from untreated HIV-1 patients did not change. When the HLA-G was measured on monocytes after antiretroviral treatment was removed, the number of peripheral monocytes expressing HLA-G was progressively decreasing. These data suggest that antiretroviral therapy is able to induce the expression of the tolerogenic molecule HLA-G on peripheral monocytes from HIV-1 seropositive individuals.