The differences between normal human lungs and the lungs of smokers are different lung colors, different anatomical structures, and different lung functions. 1. The color of the lungs is different. Long-term smoker’s lungs are black, non-smoker’s lungs are mostly pink. Because the dust particles in the smoke can lead to deepening of the lung color, in addition to frequent smoking lung blood circulation deteriorates, the lungs are often in a state of stagnation, the color of the lungs will be black. 2. The anatomical structure of the lungs is different. Frequent smokers have thickened interstitium in the lungs, thickened blood vessel walls in the lungs, and thickened lung texture during imaging. This anatomical abnormality affects the ventilation of the lungs. 3. Lung function is different. Long-term smoking causes damage and shortening of bronchial mucosal cilia, which affects the clearance function of cilia. The hyperplasia and hypertrophy of the submucosal glands of the bronchial tubes lead to an increase in mucus secretion, which obstructs the terminal bronchioles, resulting in a decrease in lung function. During pulmonary function tests, smokers have lower lung compliance, ventilation and diffusion functions, and lower partial pressure of arterial oxygen compared to normal people. Smoking is harmful to human health, especially to the respiratory system lung damage is very serious. For the sake of lung health, it is recommended to stay away from tobacco.