The aim was to study the results of using various treatment regimens for hepatic encephalopathy for patients with liver cirrhosis before and after liver transplantation and the effect on the incidence and severity of hepatic encephalopathy in the perioperative period, and on the posttransplantation course.Material and methods. Fifty four patients with cirrhosis of various etiologies and the presence of significant hepatic encephalopathy undergoing living donor liver transplantation were included in the study. In the comparison group, patients took lactulose and rifaximin. In the main group, patients took lactulose and rifaximin in combination with L-ornithine-L-aspartate in the preoperative period, and L-ornithine-L-aspartate after liver transplantation for 5 days.Results. The use of L-ornithine-L-aspartate in the complex therapy of hepatic encephalopathy led to significantly reduced time of performing the Number Connection Test, the improvement of cognitive functions in patients by the Montreal Cognitive Assessment, a decreased incidence of stage II–III hepatic encephalopathy and an increased incidence of stage 0-I hepatic encephalopathy in the preoperative period. In the postoperative period, patients of the main group showed a rapid decrease in the severe stages of hepatic encephalopathy (stage II–III) towards less severe forms (stage 0–I) on the 3rd, 5th and 7th days after liver transplantation, and also a faster recovery of cognitive functions, an earlier adequate recovery of consciousness, muscle tone, an earlier possibility of extubation, a shorter length of stay in the intensive care unit, and a decreased postoperative hospital length of stay relatively to the patients of the comparison group.Conclusion. The use of L-ornithine-L-aspartate in the combination therapy for hepatic encephalopathy in the peritransplantation period leads to a significant decrease of the incidence and severity of hepatic encephalopathy, accelerates rehabilitation of patients, reduces postoperative hospital length of stay.