It has been observed that the organ manifestations in the patients with autoimmune diseases resulted from vessels damage may be caused by CD4+CD28- T lymphocytes, which express high levels of IFN gamma and posses cytolytic activity. The increased number of these cells in the recipients of allogenic bone marrow grafts and kidney grafts was also observed. The aim of the study was to evaluate the amount of CD4+CD28- T lymphocytes in the recipients of allogenic liver grafts. The size of CD4+CD28- T cells compartment has been determined in 20 patients after liver transplantation and 20 healthy subjects as control group using two-color FACS analysis. The frequency of CD4+CD28- T cells in the liver transplant recipient was 5.65% and was significantly higher than in control group 1.4% (p < 0.001). The increased level of cytotoxic CD4+CD28- T cells may be involved in vessels damage and gradual loss of graft function.