A structural diagram of calculation of reliability of hydraulic turbines is proposed taking into account control of arameters of state of system elements, based on data of the map of setpoints of automation and process protection of hydroturbine of HPP. Failure-free operation of hydraulic unit systems and assemblies was analyzed for reliability indicators. The main elements of the system are identified. The safety of HPP operation largely depends on the reliability of the main generating equipment. Hydroturbine equipment of a hydroelectric power plant is designed for specific operating conditions characteristic for each type of hydroelectric power plant. This allows for each type of turbine to efficiently obtain the greatest amount of hydraulic power if they operate under proper conditions. Therefore, when evaluating reliability indicators, it is proposed to take into account weighting factors reflecting the degree of influence of a particular parameter on the reliability of the system. The obtained results were compared according to the proposed model and according to the regulatory methodology for assessing the probability of system failure-free operation in a generalized form. Based on the results, a model is proposed that takes into account the failures of the hydraulic unit elements to predict the probability of trouble-free operation in order to ensure the reliability of equipment operation beyond the design service life and reduce operating costs.