Objective:To detect the effects of obesity on pulmonary inflammation and function in mice. Methods:Male ICR mice were fed with high fat diet for 150 d from the 21st d postnatal after weaning to establish obese mice model(high fat group) while those in control group were given standard chow diets. Mice in high fat group with weight 10%-20% heavier than the normal were classified into overweight group;mice in high fat group with weight 20% heavier than the normal were classified into obesity group. Basic lung function was recorded;pathological HE staining and immunohistochmistry labeling macrophages(F4/80) were performed to measure lung inflammation. Results:(1)Pathological HE staining and immunohistochmistry(F4/80) of pulmonary tissues showed that inflam-matory cell infiltration in alveolar septum and around bronchus was increased in obesity group than in control group and overweight group(especially macrophages). (2)Pulmonary function(peak inspiratory flow;peak expiratory flow;50% tidal volume expiratory flow) showed no significant difference between these groups. Conclusions:Obesity enhances lung inflammation,however,makes no difference in ventilation function.