The article analyzes the influence of the institutional factor on the process of market transformations in the Russian agrarian sector from the point of view of the institutional theory, namely the transaction costs concept. The author highlights the Russian specifics and the differences of land reforms in this country from those in such countries as Japan, Germany, Scotland, Thailand, and Brazil. The paper provides an in-depth analysis of the relationships between state authorities and landowners, as well as between diverse property regimes. According to this analysis, there are two most significant factors that defined the content and result of the agrarian reforms in Russia: (1) weakness of legal institutions, (2) lack of control over realization and protection of property rights. The author concludes that high transaction costs turned to be the main obstacle during the formation of the land market in this country. Virtually total absence of government’s involvement in the minimization of transaction costs is pointed out. At the same time, according to the international experience, such involvement proved to be essential for eventual success of agrarian reform. As a result of institutional deficiencies Russia faces an absolute reduction of cultivated land and a loss of interest in land as a subject of management or as an attractive investment asset. A matter of special examination of the article is the multiplicity of property regimes in the Russian agrarian sector. They are presented by the farmers, agroholdings, mega-farms, small agribusiness, and agricultural cooperatives. The final conclusion of the author’s analysis of the existing property regimes is that all of them still lack economic viability because of the fundamental institutional deficiencies of land reform in this country.