Abstract. The article describes evolution of Technology Readiness Level (TRL) scale and analyzes prospects of using TRL methodology as an instrument of public financing of R&D and innovation in OECD. It is noted that TRL was first applied at the end of 1960s by NASA, where it was used as a means of measuring progress in technology development. In the beginning of 2000s, it has become a widespread project management tool. Advantages and limitations of the TRL scale application in R&D project management are revealed in the article. In 2010s, several countries and regions started using TRL methodology in different capacity – as an instrument of public funding of national innovation systems. EU also announced plans to build TRL into the foundation of its new innovation policy. The plans were partially implemented in the subsequent EU Framework program Horizon 2020. Application of TRL scale was limited to tender documents and applications for project funding. It was not applied in the program budget planning or in assessment of project results. The authors claim that in order to use TRL methodology in public funding at full length, it is necessary to create certain conditions. The most important of them are: a} clear definition of the stages (types) and results of scientific and technical activities in accordance with the TRL methodology and linking them with the instruments of public support; b) development and application of appropriate number of industry-specific TRL scales; c) wider usage of TRL methodology and other indices of readiness in planning, implementation and integral evaluation of the results of R&D projects; d) introduction of TRL methodology into national systems of accounting and reporting on R&D projects and development of science, technology and innovation sphere.