To assess changes of blood parameters in people living with HIV on antiretroviral therapy, a follow-up study was carried out subjects. A group of 45 subjects in ICBRA (Integrated Centre for Bioclinical Research of Abidjan) with HIV infection were recruited with a mean age was 26.1 ± 0.7 years. These Patients were followed by control of some blood parameters before initiating (J0) antiretroviral therapy. These same biological parameters were assessed after 6 (M6) and 12 (12M) months. The results of study was indicated a decrease of anaemia prevalence during follow-up ((51.1%, 42.2% and 40% respectively at J0, M6 and M12. In the same way, during treatment, microcytic hypochromic anaemia and macrocytic hypochromic anaemia were more observed. Moreover, these two types of anaemia were more revealed according to CD4 classes. In addition, the prevalence of neutropenia was observed in 55.6% at the beginning of treatment, it was decreased to 37.8% at M6. Lymphopenia was reported only in 2.2% of patients at treatment initiation. As for thrombocytopenia, it was revealed in 11.1% of subjects at treatment initiation. In the sixth and twelfth months of treatment, it was recorded respectively in 11.1% and 8.9% of subjects. According to the CD4 count, high prevalence of leukopenia to class B and class C for initiation of neutropenia and lymphocytosis to classes A and B and monocytosis all classes were observed. This study revealed a non-significant increase in CD4 count. The majority of patients had normal glucose levels during follow-up (93.4%, 95.6% and 97.8% respectively at J0, M6 and M12). Normal rate of creatinine was also indicated (73.3%, 71.1% and 84.4% respectively at J0, M6 and M12) and alanine aminotransferase levels (ALT) (88.9%, 84.4% and 82.2% respectively at J0, M6 and M12).