Introduction. The formation of an algorithm for designing mechanical systems machines in terms of reliability is considered. The algorithm is built with account for the latest publications on the standardization of reliability indices of machines and components at the initial stages of the project. The recovery cost technique, free from the need to use the exponential law when distributing reliability indices between system elements, is presented. The concepts of the required and achieved reliability factors and methods for obtaining them at different stages of the project are introduced. The possibilities of the project modification to provide a given level of reliability are considered. Research objective is to combine modern scientific developments on the standardization of reliability indices of machines, components, and methods for obtaining the required operation life with the design drafting stages.