A large number of cases of SARS-CoV-2 have been reported over the world, which makes those infected have severe symptoms while some maybe cannot be identified for lack of obvious symptoms. It is found that high levels of cytokines is linked with the severities of the virus. Apart from the increase of cytokines, moderate SARS-CoV2 patients proved a gradual reduction of antiviral and antifungal responses. During cytokine storm, upregulated cytokines would play an important role in generating adverse symptoms and it in deed has a damage mechanism. Based on the different levels of symptoms of CRS, various treatment is to be required, and IL-6 as the key cytokines that is generated among those abnormal cytokines should be paid more attention on. The thesis is hoped to be helpful for the research on treatment for CRS and conquering the virus.