Introduction: Human leukocyte antigen (HLA)-B*57:01 allele has a strong relationship with developing a hypersensitivity reaction (HSR) to abacavir (ABC). It is a well-known pharmacogenetics marker for ABC HSR. The contribution of this allele in the Moroccan HIV1 infected patients has not been established. Objective: The purpose of our study is to estimate the prevalence of HLA-B*57:01 in Moroccan HIV-1 infected patients and to evaluate HLA-B*57:01 relationship with ABC HSR Materials and methods: A total of 166 cases are enrolled in the present study and filled in questioner about demographic and clinic factors. All cases were infected by HIV-1. Their DNA samples was isolated from peripheral blood and HLA-B*57:01, was genotyped by a sequence specific primer PCR. Results: From the results obtained, we can conclude that the HLA-B * 57: 01 allele is not a common allele in Moroccans (none of HIV-infected patients expressed HLA-B*5701. HLA-B*57:01 allele), therefore hypersensitivity to abacavir appears to be rare in this population. The prescribing of ABC may don't have a risk of hypersensitivity reaction for HIV infected patients and the use routine testing for HLA-B * 57:01 would not be a cost-effective and efficient strategy in Morocco.