The article analyzes the impact of the COVID-19 pandemic on business activities in Ukraine and the world and its financial security. The analysis showed that the economy of Ukraine, like most countries in the world, has suffered significant losses from the introduction of anti-epidemic restrictions on business activities, which manifested itself in falling GDP, industrial production index, investment activity. Due to the temporary or complete cessation of business, the unemployment rate has increased significantly. The pandemic crisis also harmed enterprises' financial results, which declined significantly in all economic activities, especially in industry, transport, temporary accommodation, and catering, where the share of unprofitable enterprises reaches 73%. Thus, the problem of ensuring the financial security of business becomes relevant. The work aims to develop methodological approaches to assessing the impact of the pandemic crisis on businesses' financial security and to identify effective ways to ensure such security. The research used scientific abstraction, comparative and systematic analysis and synthesis, systematization, and logical generalization. It was determined that small and medium-sized businesses were most affected by the pandemic, where more than 60% of entrepreneurs had a strong negative impact. Large businesses suffered less, but they also suffered significant losses due to declining business activity and demand in domestic and foreign markets. The pandemic had the least impact on agriculture, which suffered the least losses, primarily due to the slight impact of restrictions on this business's activities. The paper systematized the risks arising from the pandemic crisis factors and identified their manifestations and financial consequences for the business. Studies have shown that such effects manifest themselves in the form of total or partial loss of profits, problems with debt repayment, reduced financial stability, liquidity, increased receivables, increased costs of anti-epidemic measures, and so on. Thus, the procedure for assessing the business's financial security is to take into account all the factors that shape the financial position of businesses during a pandemic crisis.