Background: To investigate the significance of IgM and IgG in the progress of COVID-19. Method: A multicenter cross-sectional study conducted in suspected and confirmed patients from four hospitals of China and a cohort study to identify the change pattern and significance in the process of COVID-19 disease. Results: A total of 571 patients were enrolled in the cross-sectional study, including 235 confirmed SARS-CoV-2 infection with 91.9% patients IgG positive and 92.3% IgM positive. 30 patients diagnosed with SARS-CoV-2 infection were enrolled in the cohort study for flowing-up in 20 days. The peak of IgM and IgG reached in 10th and 20 th day separately after symptom onset. The relationship between clinical classification and serological antibodies were analysed. The positive rate of COVID-19 IgG and IgM increased along with the clinical classification and the delay of treatment time. Conclusion: We demonstrated the kinetics of IgM and IgG SARS-CoV-2 antibody in COVID-19 patients, which may contribute to explain the results of IgM and IgG SARS-CoV-2 antibody test and predict the prognosis of COVID-19.