Secondhand smoke is passive smoking, the harm is not less than firsthand smoke, secondhand smoke also contains nicotine, tar, harmful gases, and harmful dust, particles, is also one of the more important factors that cause respiratory disease. Second-hand smoke every day is a potential hazard to the body, so we should start from the following aspects: 1, we should try to admonish first-hand smokers, inform them of the hazards of smoking and the impact on others, and try to help them successfully quit smoking and eliminate the production of first-hand tobacco smoke. 2, in the case of really can not completely eliminate first-hand smoke, do a good job of personal protection, try to reduce the time to enter the environment of second-hand smoke. Indoor windows should be diligently opened and ventilated to allow air circulation and reduce the concentration of indoor tobacco smoke, and individuals can wear protective masks. In addition, if there is an air conditioner can play to the ventilation mode, if there is a new air system can always open, or you can also buy air purifiers, through the role of purification to reduce the concentration of tobacco in the air.