There are many kinds of situations that cause blood when coughing, usually including the following aspects: 1, it may be that the patient coughs too hard when he coughs, resulting in the rupture of capillaries, which will be brought out when coughing up sputum, and the symptoms can be significantly relieved by taking cough suppressing and expectorant drugs.2, the situation of coughing with blood may also be that the patient’s respiratory system has a certain kind of disease, for example, acute, chronic bronchitis, bronchial dilatation, etc. When the respiratory tract is repeatedly stimulated by inflammation, it will produce blood. Bronchitis, bronchial dilatation, etc., when the respiratory tract is repeatedly stimulated by inflammation, blood will be produced. 3, due to lung tumors will make the local blood supply increase, when the tumor invades the supply blood vessels of the lungs or the trachea, coughing up sputum with blood will also occur.