The article attempts to examine the features of the contemporary development of historiography of scientists of the Union State of Russia and Belarus on the problems of Belarus-Russia relations (1991-2016). The historiography of the Union State is understood as the latest research of Russian and Belarusian researchers that studies areas of cooperation of two countries. These studies were performed in the field of history and political science, economics and sociology, international relations and law, philosophy and psychology. The problems of Russian-Belarusian relations as well as the problems of Belarusian-Russian integration are reflected in the latest historic and historiographic publications. At the same time, it is necessary to say that at the moment there are no research publications that show the latest Russian, Belarusian and foreign historiography on the development of Belarus-Russia relations in 19912016. The historiographic sources the author used represent the current state and level of scientific thought of the research communities of Russia and Belarus on the problems of interstate cooperation in the following spheres of interaction: energy sphere, military cooperation, scientific cooperation and Belarusian-Russian cooperation in the information sphere. Moreover, the article lists the main Russian and Belarusian universities, research and analytical centers, leading scientific institutes that engage in studying the above-mentioned problems. A complex and multilateral study of the phenomenon of the formation and development of Belarus-Russia relations seems extraordinarily important in contemporary circumstances. At present, the necessity of a profound and objective comprehension of the development of modern international relations in the post-Soviet space is actualized in connection with a periodical unfavorable aggressive external-politic and external-economic conjuncture. The publication of this article can be viewed not only as an attempt to fill some research lacunas in science, but also as a peculiar form of historiograpic mediation between modern researchers. The author concludes that the results of a lot of perspective scientific research and developments have not found practical application in the development of external-politic and external-economic courses of Russia and Belarus and in the development of integration interaction between the countries yet.