At the end of December 2019, some hospitals in Wuhan, Hubei, China found unexplained pneumonia cases one after another. On January 12, 2020, World Health Organization officially named the new coronavirus that caused the outbreak as “2019 new coronavirus”. The National Health Committee of China has organized experts to compile a “pneumonia diagnosis and treatment program for new coronavirus infection” to guide the prevention, control, diagnosis and treatment of the disease. However, due to the limited knowledge of the disease, there are still many problems to be solved in the diagnosis and treatment of the disease. We reviewed the researches on coronavirus infections related to severe acute respiratory syndrome and Middle East respiratory syndrome, combined with our own experience in diagnosis and treatment, and proposed some thoughts on several unclear hot issues such as the mode of disease transmission, the incubation period, the practical application of diagnostic standards, and the choice of treatment drugs in the diagnosis and treatment plan.