The paper is devoted to the analysis of the role of the dollar in the world economy and its formation as a world reserve currency. Based on the methodology of the school of world-system analysis (J. Arrighi, S. Amin, I. Wallerstein, R.S. Dzarazov), the author reveals the mechanism for using the dollar as one of the instruments of unequal exchange between the center and the periphery of the economy within the American systemic capital accumulation cycle. Based on a comprehensive empirical analysis, an assessment is made of the trends in the de-dollarization of the world economy in the 21st century. It was found that despite the devastating consequences of the global crisis of 2007–2009. caused by the hypertrophied development of the financial sector of the US economy during the global crisis, the dollar retained a key role in the international reserves of states, in trade and exchange operations in the world economy. In particular, the Russian economy, despite the statements of the authorities about moving towards abandoning the dollar, nevertheless remained highly dependent on it, only partially replacing US dollars with the euro. Real de-dollarization 2022-2023 in Russia became a necessary measure for business, and was associated with the partial blocking of Russian correspondent accounts in Western banks.