The article deals with the method of comprehensive assessment of the investment attractiveness of a startup project and the criteria for its effectiveness. Investment attractiveness of a startup is such an economic category, which is a complex indicator of objective and subjective characteristics of a startup, characterized by the efficiency of using the property of the enterprise, its solvency, financial stability, the ability to self-development on the basis of increasing the return on capital, quality and competitiveness of products, and reflecting the feasibility of investing funds. To select the optimal criteria for the investment attractiveness of a startup and develop the necessary procedures for their use, the first part of the article considers the problems in the activities of enterprises that can affect their investment attractiveness. In relation to the selected components, the criteria for assessing their condition and the degree of influence on investment attractiveness are determined. When selecting a startup project, the authors proposed a number of important criteria, of which at least 6 were singled out. Their availability and sufficiency are necessary conditions for its intended implementation. Further, the authors propose a single method of comprehensive assessment of the level of investment attractiveness of a startup. The presence and possession of such a technique will allow the head to make up for the lack of experience in the implementation of startup projects and the development of new innovative ideas, as many, falling into force majeure experience confusion and panic, which often leads to significant financial losses. To do this, a number of elements that have the greatest impact on investment characteristics are pre-allocated in the structure of the proposed business startup. Thus, this study helps potential investors of financial resources in new start-up projects to carry out forecasting in advance and avoid the main problems that arise in front of them when applying the developed methodology of their assessment.