With the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, the incidence of coronavirus disease (COVID-19) increases each day. To date, there is no specific anti-SARS-CoV-2 drug. The usual approach to treating COVID-19 is treating its symptoms. However, this approach is limited by the different conditions of each area. We treated a 57-year-old man who was initially diagnosed with a severe type of the infection, but he progressed to a critical condition and eventually died. We learned valuable lessons from this case. The first lesson is the need to use immediate invasive mechanical ventilation if there is no obvious improvement after using non-invasive ventilation for several hours, which directly affects the prognosis. Another lesson is the risk involved in transferring severe COVID-19 patients. In the process of transfer, various threats may be encountered at any time. Thus, accurate assessment of the patient's condition and strict medical conditions are highly required. During the patient's 25-day treatment, we performed cardiopulmonary resuscitation twice. Currently, many patients require invasive mechanical ventilation and transfer to a superior hospital. We hope our findings will provide some advice and help for treating severe and critical COVID-19 cases.