Aim. To determine the role of microcirculation disorders in association with the C774T polymorphism of the eNOS gene in the progression of acute pancreatitis. Materials and methods. We investigated 90 patients with acute pancreatitis. In 30 patients of group 1, a mild course of acute pancreatitis was noted, in 30 patients in group 2 – moderate severity of the disease, in 30 patients in group 3 – severe acute pancreatitis. The state of microcirculation was evaluated by LACK-02 apparatus (NPO “Lazma”, Russia). The molecular genetic testing of eNOS gene polymorphism ( C774T ) was performed using DNA samples (isolated from peripheral blood) by real-time polymerase chain reaction (CFX96 Touch™ Real-time PCR Detection System, USA). The study design is prospective. The evidence level – II. Results . It has been established that in the early stages of acute pancreatitis occur microcirculatory disorders (a depression of the microcirculation index, coefficient of variation, and microcirculation efficiency index), which associated with the severity of the disease. In mild and moderate forms, these changes were stopped by using standard therapy to sixth day of illness. In patients with acute severe pancreatitis these changes persisted. It should be noted that microcirculation disorders were more significant in patients with the T774T polymorphism of the eNOS gene. The most frequent (56.3 %, C' = 0.880, p = 0.001) such pathological phenomena were registered in severe form of the disease, which is an important argument for adjusting personalized therapy. Conclusion. The presence of T774T polymorphism of the eNOS gene in patients with acute pancreatitis, associated with an increased level of nitric oxide production, leads to the development of microcirculatory disorders, which should be recognized as one of the risk factors for disease progression and development of complications.