Rostov-on-Don, Rostov Region, Russia Zhigunova А.V. Rostov State Transport University Rostov-on-Don, Rostov Region, Russia Ovsyannikova I.P. Rostov State Transport University Rostov-on-Don, Rostov Region, Russia Logvinova I.V. Rostov State Transport University Rostov-on-Don, Rostov Region, RussiaAbstract-In the conditions of non-stationary economy during the investment analysis there is a need to take into account the factors of changes in the value of money in time, uncertainty and risk. This requires a comprehensive and systematic analysis based on the logical and mathematical concept of the time value of money and discounting in the formation of the evaluation apparatus of investment projects. The authors propose the principle of logical-mathematical concept, which consists in the fact that you can only discount the increased amount, not capital gains. It is argued that it is mathematically incorrect to compensate for the impact of inflation, risk and alternative cost of capital on the cash flows of a real investment project by discounting cash inflows. The principal point in assessing the effectiveness of investment projects is the organization of a clear algorithm of cash flows. The authors have compiled such an algorithm. Keywords-investment project, the time value of money, uncertainty, risk, methods of assessing the effectiveness of investment projectsI.