Objective: This study tested wether preterm infants of <32 gestational weeks (GWs) with a blood gas derangement within 7days of life are at increased risk for moderate and severe bronchopulmonary dysplasia (BPD). Method: 236 preterm infants with <32 GWs from January of 2017 to December of 2019 were included in this study. First, univariate analysing determined wether there existed associations between BPD (moderate and severe) and blood gas values, clinical characteristics, interventions, daily given liquid and eneregy within 7days of life. Then multivarariate regession analysis was performed to know wether there were relationships between BPD (moderate and severe) and risk factors between which and BPD (moderate and severe) univariate analysing showed that P value was less than 0.1. Results: From univariate analysing, we found that PaO2, PaCO2 and HCO3 in 7th day of life, cesarean section (OR=0.508, 95%CI:0.275-0.94), getational age (GA, OR=0.163, 95%CI:0.077-0.344), birth weight (BW, OR=0.122, 95%CI:0.054-0.273), PDA (OR=2.839, 95%CI:1.1463-5.508), early onset infection (OR=3.00, 95%CI:1.483-6.069), and mechanical ventilation (MV, OR=4.562, 95%CI:2.405-8.653) were significantly associated with moderate and severe BPD. Because there existed close relationship between GA and BW (R=0.642, P=0.000) and BW dispersion was big in this group, we excluded BW in multivariate analysing. From multivariate analysing, besides GA (Exp (B)=0.176, 95%CI:0.08-0.389) , MV (Exp (B)=3.515, 95%CI:1.746-7.076), PaO2 (Exp (B)=0.468, 95%CI:0.226-0.969) in 7th day of life was the independent risk factor for moderate and severe BPD in the preterm infants of <32 GWs.Conclusion: Preterm infants of <32GWs with blood gas derangements within 7days of life could be at risk of moderate and severe BPD.