Background It remains unclear if pediatric patients with acute or chronic lung diseases benefit from chest physiotherapy (CPT) during spontaneous breathing. The electrical impedance tomography (EIT) offers the opportunity to assess treatment effects of CPT on regional ventilation distributions. Methods We conducted a prospective feasibility study between 10/2023 to 05/2024. Pediatric patients with need for active or passive CPT were screened. EIT measurements were performed at (T1) immediately prior to CPT intervention, and (T2) within 30 minutes after CPT intervention. Results Overall, 25 patients were enrolled, with two patients enrolled twice at different admissions, resulting in 54 EIT-measurements. The mean horizontal center of ventilation (CoVx) and the mean vertical CoVy were equally distributed at T1 and T2, without any difference seen when subdividing for mode of CPT. The mean global inhomogeneity index (GI) decreased from 0.38 to 0.36 (∆GI: -6%, p=0.939) in the overall cohort, with a significant decrease between T1 and T2 in patients with active (∆GI: -10%, p=0.015), but not in patients with passive CPT (∆GI: +6%, p=0.199). In patients with a localized pulmonary finding in the radiologic assessment (n=10) we observed a markedly increase of the proportional ventilation distribution of the affected lung side after CPT (T1:44% vs. T2: 48%, p=0.057). Conclusion EIT seems feasible to monitor changes in regional ventilation distribution after CPT in pediatric patients. Patients with localized pulmonary radiological findings and patients after active CPT seems to benefit most from CPT, whereas there is a subset of individuals with no response to CPT.