The article reflects the results of studying platelet parameters in HIV-positive patients with different types of stroke.Aim. To identify changes in laboratory parameters of a complete blood count which characterize the morphofunctional features of platelets in stroke among HIV-positive patients.Materials and methods. 110 HIV-positive patients who received treatment for stroke in hospitals of the Tyumen region were examined. The study of blood parameters was carried out at the analyzer Sysmex XE2100 (Japan). Blood sampling was carried out on the day of patients admission.The number of platelets and platelet indices were analyzed: MPV – mean platelet volume, PDW – platelet distribution width, PCT – plateletcrit and P-LCR – platelet large cell ratio. The control group consisted of 117 patients. The signifcance of the differences was determined at the twotailed signifcance level of p < 0.05.Results. There was a signifcant decrease in the number of platelets (p < 0.05), in average, on 34.3% among patients with hemorrhages and HIV infection. Among patients with ischemic stroke this decrease was less pronounced (p = 0.05). A signifcant decrease in plateletcrit was established among patients with intracranial hemorrhages, while it did not change signifcantly among patients with cerebral infarction. During evaluation of other platelet parameters, no signifcant differences were found between patients in experimental and control groups. The coeffcient of giant platelets prevailed by one and a half times in patients with hemorrhages associated with HIV infection, which turned out to be beyond the statistical signifcance.Conclusion. The presence of HIV infection leads to a more pronounced, reliable decrease in the number of platelets and plateletcrit among patients that have acute phase of the development of hemorrhagic stroke than in patients with cerebral infarction. The development of intracranial hemorrhage among HIV-positive patients is characterized by an increase of blood platelets with a high volume, the level of which increased by one and a half times being beyond the statistical signifcance and having as a leading mechanism the intensifcation of platelet formation in the bone marrow.