Many microbial metabolites, especially butyrate, found in the intestinal flora, are extremely important in regulating systemic and pulmonary immune and inflammatory responses and have a wide range of anti-inflammatory and immunity enhancing functions. Improving intestinal micro-ecology via like butyrate supplementation may partially mediate the effects of SARS-CoV-2 on the both local gastrointestinal response and systemic immune response of the host, and thus be a target for COVID-19 prevention and treatment.