The COVID-19 epidemic in 2020 fully exposed the disadvantages and crisis of the capitalist system. On the basis of reflecting the capitalist system，the left wing of every country believes that the profit-oriented capitalist mode of production has led to the spread of the epidemic. The epidemic has made the inequality of capitalist society more prominent，and the long-term implementation of neoliberal policies has made capitalist system facing more and more serious crisis. In contrast to the capitalist system，the performance of the socialist countries in fighting the epidemic has clearly demonstrated the superiority of the socialist system and aroused people’s interest in socialist alternatives.