Introduction: Patients with bronchopulmonary dysplasia (BPD) exhibit significantly reduced lung function compared to healthy children. However, due to the challenges of performing spirometry in children under 5 years, functional behavior remains poorly characterized, and the utility of impulse oscillometry (IOS) in this population, particularly at high altitude, is unknown. Objective: To compare IOS variables between pediatric patients under 5 years of age with a history of BPD and healthy children residing in a high-altitude city. Methods: This retrospective, analytical, cross-sectional study included pediatric patients aged 3 to 5 years with a history of BPD, evaluated between 2019 and 2023 in Bogotá, Colombia. Healthy children of the same age and sex, previously included in a study of IOS reference values at our institution, were used as controls. Results: A total of 111 patients were included, 71 (64%) with BPD. The mean gestational age in the BPD group was 31 weeks (IQR 28–32 weeks), with a mean birth weight of 1350 grams (IQR 993–1800 grams). Most BPD patients exhibited elevated peripheral airway resistance (84.5%, n=60). Pre-bronchodilator mean values for R5, R20, R5-R20, X5, and AX were significantly higher in the BPD group. Conclusions: Children with BPD have elevated resistance levels and more negative reactance in the airways compared to healthy term children. This study identifies a characteristic functional pattern in children with BPD, which may be defined as an obstructive pattern without bronchodilator response. Longitudinal studies are needed to establish functional trajectories in this population.