As the saying goes: “fall and winter fog is a killer knife”. Since the fall, the haze once again began to run amok, not only on people’s travel inconvenience, but also become a major “killer” of human health. According to research, the haze contains harmful particles, toxic substances up to more than 20 kinds, including acids, alkalis, salts, amines, phenols, etc., as well as dust, pollen, mites, influenza viruses, tuberculosis bacilli, pneumococcus, etc., and its content is dozens of times that of the ordinary atmospheric water droplets. Whether haze can cause cancer has once become a hot topic of discussion, living under the haze, our fear of lung cancer is increasing day by day. Every November is the “Global Lung Cancer Awareness Month”, and lung cancer has the highest incidence and mortality rate among malignant tumors, and is called “the world’s number one cancer killer”. In the past 30 years, the mortality rate of lung cancer in China has increased by 465%, and lung cancer has become the first cause of death of malignant tumors in China, accounting for 22.7% of all malignant tumor deaths. At present, the incidence of lung cancer is increasing by 26.9% per year. If effective control measures are not taken in time, it is expected that by 2025, the number of lung cancer patients in China will reach 1 million, becoming the first lung cancer country in the world. The haze is very close. Is lung cancer still far away? In the past, it was believed that the two main factors leading to lung cancer were occupational exposure and smoking. But nowadays, in most cities in China, with the increasing health awareness of people, the number of smokers is decreasing and the working environment has been greatly improved, but the incidence of lung cancer is still showing a rising trend, which fully explains that lung cancer is related to urban atmospheric pollution and carcinogenic substances contained in soot. Haze can cause physical and chemical stimulation and bacterial infection to human lungs. after PM2.5 enters the alveoli, the haze hinders the ultraviolet rays, so the airborne germs are brought into the lungs along with it, thus causing damage to the alveoli. The alveoli is the main part of the gas exchange in the lungs, is the barrier between the air and the blood, once stimulated, the barrier is damaged is prone to inflammation, and repeated inflammatory stimulation may cause cancer. Academician Zhong Nanshan believes that the haze weather leads to lung cancer incidence even fiercer than nicotine. Control of environmental pollution can not be delayed! So, what should we do about the status quo of haze and the established fact of high incidence of lung cancer? Through early surgery, the 5-year survival rate of early lung cancer patients can reach more than 70%. Early detection, early diagnosis and early treatment is the key to improve the survival rate of lung cancer, therefore, lung cancer screening should not be delayed!