H7N9 is an avian influenza virus, a subtype of avian influenza, a novel reassortant virus. The H7N9 avian influenza virus is weakly pathogenic to birds, and is easy to transmit among birds and difficult to detect, thus increasing the chance of human infection. The virus is heat sensitive but resistant to low temperatures. The source of infection is mostly birds carrying the H7N9 avian influenza virus, and the main means of transmission is through respiratory transmission and close contact with feces or secretions of infected birds, or through direct contact with virus-contaminated environments. People infected with the H7N9 avian influenza virus may experience flu-like symptoms, including cough, sputum, fever, muscle aches, headache, vomiting or diarrhea. In severe cases, the disease develops rapidly, with respiratory distress, which may progress to septic shock and ARDS. In mild cases, only symptoms of upper respiratory tract infection and fever are present. Infected with H7N9 avian influenza virus should be isolated as early as possible and treated with antiviral drugs; those with high fever should be given medication to lower their temperature, those with hypoxia should be given oxygen therapy, and those with severe cough and phlegm should be given cough suppressant and expectorant drugs to relieve their coughs and symptomatic treatments, and so on. We should pay attention to the prevention of avian influenza in our life, wash our hands diligently, ventilate more, go to the poultry market less often, wear a good mask, and eat poultry meat or eggs should be cooked thoroughly. Exercise properly to enhance personal resistance. If H7N9 avian influenza virus infection is confirmed, early isolation and standardized treatment are recommended to minimize adverse effects.