Objective：To analyze and summarize the treatment status and the incidence of bronchopulmonary dysplasia(BPD)in very preterm infants(VPI)and extremely preterm infants(EPI)in the latest 3 years. Methods：A retrospective analysis was performed in 547 premature infants，with gestational age less than 32 weeks and survival time≥28 days，who were admitted to Neonatal Medical Center of Children’s Hospital of Nanjing Medical University from January 2018 to December 2020. According to clinical diagnosis， they were divided into BPD group(n=126)and non -BPD group(n=421). The two groups were compared comprehensively，and the clinical data and incidence of BPD among the latest 3 years were compared and summarized. Results：The gestational age of the BPD group was 28.57±1.49 weeks，and the EPI with gestational age less than 28 weeks accounted for 31.7%，while that of the non -BPD group was 30.05±1.39 weeks，and the EPI was only 8.1%(P ＜ 0.05). The birth weight of BPD group was 1132.18±251.25 g，and the extremely low birth weight(ELBW)infants with birth weight ＜ 1 000 g accounted for 28.6% ，while that of non-BPD group was 1384.47±267.44 g，and ELBW infants only accounted for 6.4%(P ＜ 0.05). The proportion of 5 min Apgar score ≤ 7 and resuscitation in the delivery room were significantly higher in BPD group(P ＜ 0.05). The first dose of the pulmonary surfactant was significantly higher(P ＜ 0.05)and the rate of usage times ≥ 2 times was lower(P ＜ 0.01)in the non -BPD group. The the proportion of invasive mechanical ventilation and non-invasive ventilation，duration of ventilation and incidence of pulmonary hemorrhage were significantly increased in BPD group(P ＜ 0.001). The length of hospitalization was significantly longer and total cost was higher in BPD group (P ＜ 0.05). Longitudinal analysis showed the total incidence of BPD was 23.0% in three years，while it was 28.8% in 2019 and 15.3% in 2018(P ＜ 0.05)，there were no significant differences in the proportion of invasive mechanical ventilation，EPI and ELBW(P ＞ 0.05)， but the ELBW in 2018 was significantly higher than other years(P ＜ 0.05). Conclusion：It is necessary to monitor and track the early situation of EPI and ELBW，and pay more attention to the standardized application of PS in the early stage，to further reduce BPD and improve the prognosis greatly.