Complications of the novel coronavirus can involve the respiratory system, urinary system, cardiovascular system, blood system and digestive system. 1. Respiratory system, after the virus enters the body, it will first attack the cells in the lungs of the patients, and some of the patients will have different degrees of respiratory difficulties, and in serious cases, sequelae such as pulmonary fibrosis will occur. 2. Urinary system, after attacking the kidneys, the virus will damage the renal function of patients. 3. Cardiovascular system, mainly the cardiac muscle cells are attacked, arrhythmia occurs, and in serious cases, changes such as myocardial fibrosis will occur. 4. Blood system, due to the damage of endothelial cells of blood vessels, some patients will have thrombus formation in the body and thus lead to blood vessel obstruction. 5. Digestive system, manifested by nausea, vomiting and indigestion and other symptoms.