Objective：To explore the characteristics of cardiopulmonary function in bronchopulmonary dysplasia（BPD） complicated with pneumonia. Methods：Seventy-eight infants from Shenzhen Chil－dren’s Hospital were recruited from January 2012 to June 2013 and were divided into observation group，control group 1（BPD without pneumonia），control group 2（health infants without BPD and pneumonia）. Cardio-pulmonary function of three groups was detected. Color Doppler ultrasonography was used to detect cardiac function and ultrasonic flow meter was used to detect lung function. The diagnosis of pulmonary hypertension（PH） was made based on the velocity of tricuspid valve regurgitation（TR）≥3 m/s，left-deviated interventricular septum and right ventricular hypertrophy with chamber dilation. Results：①cardiac function：twelve cases of PH were observed in observation group while no case in control groups. Systolic pulmonary artery pressure（sPAP） was higher in observation group than in control groups（P<0.001）. Pulmonary vascular resistance（PVR）was higher in observation group than in control groups（P<0.001）. PVR of control group 1 was higher than that of control group 2（P<0.001）. The acceleration time and right ventricular ejection time（RVET） were lower in observation group than in control groups（P<0.001）. The sPAP and PVR of PH group were higher than those of non-PH group（P<0.001）. The AT and RVET of PH group were lower than those of non-PH group（P<0.001）. ②lung function：The respiratory rate（RR） was higher in observation group than in control groups（P<0.001）. The ratio of time to peak tidal expiratory time and expiratory time（Tpef/Te），the ratio of time peak expiratory volume and expiratory volume（Vpef/Ve），expira－tory flow at 75%，25% of lung volume（TEF75，TEF25），expiratory flow at 25% of lung volume to peak expiratory flow（25/PF） of observa－tion group were lower than those of control groups（P<0.05）. There was no difference between PH group and non-PH group in RR（P=0.69）. The Tpef/Te，Vpef/Ve，TEF75，TEF25，25/PF of PH group were lower than those of non-PH group（P<0.05）. Conclusion：Moni－toring cardiopulmonary function is beneficial for BPD patients complicated with pneumonia，through which patients can know cardiopul－monary injury degree，detect PH at early stage and reduce mortality to some extent.