Coinfection with the human immunodeficiency virus (HIV) and Epstein–Barr virus (EBV) represents a current biomedical problem. The purpose of the study was to evaluate blood leukocyte EBV detection rate and viral load in adult HIV-infected patients. Materials and methods. There were examined blood leukocytes collected from 138 HIV(+) and 68 HIV(–) individuals aged 20–69 years. Statistical analysis was carried out differentiated according to the stages of HIV infection, the CD4+ T-lymphocyte count, and adherence to antiretroviral therapy. Results. It was shown that EBV DNA was detected significantly more often in HIV(+) vs HIV(–) individuals (70.3±3.9% and 48.5±6.1%, p = 0.008), with EBV viral load comprising 18 [5; 139] versus 2 [1; 3] copies/105 cells (р 0.001), respectively. It has been shown that the group of HIV(+) patients is heterogeneous in the frequency of EBV detection and viral load, with the peak EBV frequency (86.7±6.2%) and DNA (121 [34; 252] copies/105 cells) level observed in “naive” patients with severe immunodeficiency. Among “experienced” patients receiving therapy, the relative risk of detecting EBV DNA with low treatment adherence was significantly higher compared to those who developed high adherence (р 0.05). When the HIV viral load reached undetectable level, EBV DNA concentration was significantly lower where HIV RNA was detectable (1 [0; 8] versus 15 [1; 162] copies/105 cells, р 0.001). Detection of EBV DNA is associated with higher HIV viral load level and lower CD4+ T-lymphocyte count compared to patients with undetected EBV DNA. A relationship has been established between the CD4+ T-lymphocyte count in HIV(+) patients and the likelihood of active EBV infection. A threshold cut-off of 200 cells/μl was determined. CD4+ T-lymphocyte count 200 cells/μl vs ≥ 200 cells/μl (р 0.001) is associated with a 3.3-fold higher risk of detecting active EBV infection. Conclusion. It is necessary to continue interdisciplinary research to improve early diagnostics of EBV-associated diseases in HIV-infected individuals.