The article contains the authors methodological approach to quantify the level of financial cooperation between the worlds largest States, Russia and China, using the original index - index of the Russian-Chinese financial cooperation, based on the proposed three-level system of indicators and the use of the method of entropy. The analysis of the dynamics of the Russian-Chinese financial cooperation index for the period 2013-2019 allows us to conclude that the relations between the two states are in a stable positive vector of development.