Main directions of improving the strategy of Ukraine's external debt management based on the results of the assessment of the main indicators of external state debt in relation to the criteria of economic security and the impact of external debt on key macroeconomic indicators are substantiated in the article. According to the results of the regression analysis of the relationship between main macroeconomic indicators and indicators of external debt, it was concluded that the external debt has an ambiguous impact on the economy of Ukraine. The hypothesis about the negative consequences of increasing the external state debt for the economy of Ukraine has not been fully confirmed. Based on the analysis of the data for 2008-2020, the direct impact of changes in external debt on GDP in actual prices, as well as the direct impact of gross external debt on changes in GDP per capita was identified. This confirms a positive role of external borrowing in ensuring Ukraine's economic growth. At the same time, the inverse dependence of Ukraine's GDP on changes in external debt per capita and the ratio of total payments to service external debt to state budget revenues was revealed. The dependence of GDP per capita on the ratio of total external debt service payments to state budget revenues is also inverse. The results of the study suggest an ambiguous impact of external debt on the national economy, which necessitates effective management of the external debt. The Long-Term Strategy for Ukraine's External Debt Management until 2030 should become an important institutional tool for reducing threats to the country's economic security arising from the growing debt burden. The purpose of the proposed Strategy is to minimize the cost of servicing external debt in the long run and reduce the level of relevant risks.