© TÜBİTAK.Background/aim: To characterize the clinical course of noninvasive positive pressure ventilation (NIPPV) and high flow humidified nasal cannula ventilation (HFNC) procedures; perform risk analysis for ventilation failure. Material and methods: This prospective, multi-centered, observational study was conducted in 352 PICU admissions (1 month-18 years) between 2016 and 2017. SPSS-22 was used to assess clinical data, define thresholds for ventilation parameters and perform risk analysis. Results: Patient age, onset of disease, previous intubation and hypoxia influenced the choice of therapy mode: NIPPV was preferred in older children (p = 0.002) with longer intubation (p < 0.001), ARDS (p = 0.001), lower respiratory tract infections (p < 0.001), chronic respiratory disease, (p = 0.005), malignancy (p = 0.048) and immune deficiency (p = 0.026). The failure rate was 13.4%. sepsis, ARDS, prolonged intubation, and use of nasal masks were associated with NIV failure (p = 0.001, p < 0.001, p < 0.001, p = 0.025). The call of intubation or re-intubation was given due to respiratory failure in twenty-seven (57.5%), hemodynamic instability in eight (17%), bulbar dysfunction or aspiration in 5 (10.6%), neurological deterioration in 4 (8.5%) and developing ARDS in 3 (6.4%) children. A reduction of less than 10% in the respiration within an hour increased the odds of failure by 9.841 times (OR: 9.841, 95% CI: 2.0021–48.3742). FiO2 > 55% at 6th hours and PRISM-3 >8 were other failure predictors. Of the 9.9% complication rate, the most common complication was pressure ulcerations (4.8%) and mainly observed when using full-face masks (p = 0.047). Fifteen (4.3%) patients died of miscellaneous causes. Tracheostomy cannulation was performed on 16 children due to prolonged mechanical ventilation (8% in NIPPV, 2.6% in HFNC) Conclusion: Absence of reduction in the respiration rate within an hour, FiO2 requirement >55% at 6th hours and PRISM-3 score >8 predict NIV failure.