On the occasion of the 300th anniversary of the Russian Academy of Sciences, the Free Economic Society — VEO of Russia, is preparing a series of articles devoted to members of the academy who actively collaborated with VEO. Academician Sitaryan S.A. entered the economic history of Russia both as a prominent theoretical scientist, and as a talented organizer of economic reform processes, and as an active participant in the life of VEO. The article analyzes the scientific views of Academician S. Sitaryan on the problems of reforming the Soviet economy, starting with the «kosygin reform» and up to the reform of the late 80s of the twentieth century. The role of academician S. Sitaryan is revealed. in approving value categories in the practice of managing the national economy. The contribution of S. Sitaryan to the theory of analysis of macro- and microeconomic processes is shown; organization and assessment of the effectiveness of foreign economic relations; building rational and optimal budgetary relations between the center and the regions.