There is a risk of infection from kissing a TB patient, and the risk is highly dependent on whether the TB patient is excreting bacteria and whether he or she is coughing, sneezing, or talking loudly. Tuberculosis is transmitted through the respiratory tract by air droplets. When a TB patient who has excreted bacteria coughs, sneezes or speaks loudly, the secretions in the lungs carry Mycobacterium tuberculosis bacteria, which float in the air and adhere to the dust of the air and may lead to Mycobacterium tuberculosis infection when inhaled by a healthy person. So when kissing, the other party does not cough, sneeze, talk loudly, and do not discharge phlegm, the probability of contact is relatively small. And if kissing for a long time inevitably excludes Mycobacterium tuberculosis by coughing and other acts, there is a possibility of transmitting tuberculosis to the other person. Because of the possibility of transmission, the following points should be done: First, patients with tuberculosis must be actively treated to reduce infectivity. Second, avoid prolonged kissing. Third, try to avoid kissing when there is coughing and sneezing. Fourth, pay attention to ventilation indoors frequently to keep reducing the concentration of Mycobacterium tuberculosis in the air.