Aim of the study: To evaluate clinical outcome and respiratory function in patients with congenital lobar/segmental emphysema (CLE/CSE) treated conservatively. Methods: In this single-centre retrospective study we included patients ≥5-year-old with a diagnosis of CLE/CSE, treated conservatively (diagnosis from 1990). We assessed demographic/anthropometric data, clinical outcome, pulmonary function tests (PFT) analyzed according to Global Lung Initiative. GraphPadPrism® (California, USA) was used for statistical analysis. Main results: Sixteen patients were enrolled (median age 9.3y; range 5-17): 13 had a prenatal diagnosis, 3 showed symptoms at birth. On chest computed tomography (CT), performed in the first 6 months of life, 9 children had lobar emphysema and 7 segmental emphysema. All patients showed a good growth, 14 were asymptomatic, 1 had recurrent respiratory infections and wheezing, 1 had allergic asthma. In 14 patients we performed PFT (median value): FVC 93.87%pred (IQR: 85.24; 107.69), Z-Score -0.52 (IQR: -1.39; 0.77); FEV1 93%pred (IQR: 78.75; 102.23), Z-Score -0.58 (IQR: -1.92; 0.34); RV 112.48%pred (IQR: 102.26; 137.70), Z-Score 0.25 (IQR: 0.05; 0.79); FRC 106.55%pred (IQR: 94.20; 111.04), Z-Score 0.31 (IQR: -0.29; 0.67); TLC 101.44%pred (IQR: 86.98; 113.25), Z-Score 0.11 (IQR: -0.96; 0.97), RV/TLC 122.94%pred (IQR: 113.52; 144.16), Z-Score 0.54 (IQR: 0.34; 1.01). Conclusions: Our data show that patients with CLE/CSE treated conservatively have a good clinical and functional outcome. Nonetheless, due to the short follow-up, further larger studies are needed to evaluate outcome into adulthood.