Market subject is the carrier of economic power, and safeguarding market subject means safeguarding social productivity. The COVID-19 epidemic has dealt a heavy blow to the market players in China. As the center of China's economic and social construction, how to protect and stimulate all kinds of market players has become a major issue facing us at present. This paper first analyzes the challenges faced by various market players under the epidemic situation, then analyzes the opportunities brought by these challenges, and finally puts forward some countermeasures and suggestions to promote the development of market players, such as increasing policy support, improving and optimizing the business environment, vigorously stimulating various market players, giving full play to the role of entrepreneurs and promoting enterprise innovation.