This article has three parts. In the first part government debt is analyzed as the stock of government financial obligations in Russia and the USA. Obligations denominated in foreign currencies and direct credits are left behind because they are practically non-existent in US government financial transactions. Also excluded from the analysis are debts incurred by stateowned corporations, which are part of the corporate sector of the System of National Accounts. In the second part government debt is analyzed as a result of financial flows (borrowings) which show how debt changes over time. In both parts Russia is compared with the USA in terms of proportions between federal and sub-federal debts, domestic and foreign debts (Russia only), marketable and non-marketable debts as well as domestic and foreign participants of government securities markets. The third part of the article presents standard methodology of debt sustainability analysis and some results of Bohn test of debt sustainability for both countries.