Objectives: The aim of this study was to examine the influence of tracheobronchial tree measurements on the treatment outcome of critically ill patients and the connection of measurements with the length of ICU stay, hours spent on mechanical ventilation, the development of nosocomial pneumonia and patient’s outcome. Study Design: Cross-sectional study Participants and Methods: The study included 42 patients hospitalized at Intensive care unit of the Clinical Hospital Centre Osijek who had a chest CT during 2019. and 2020. CT scans were analysed and tracheobronchial tree measurements were recorded. Data on the length of ICU stay, hours spent on mechanical ventilation, the development of nosocomial pneumonia and the final outcome of the patients were obtained from the BIS, disease history analysis and therapeutic lists. Statistical analysis was performed using Mann Whitney U test and Pearson’s and Spearman’s correlation coefficient. Results: The median age of patients was 60. Most patients were admitted to the ICU through the emergency department. Due to respiratory insufficiency, which was the most frequent comorbidity, 90 % of the patients were mechanically ventilated, and 48 % of the patients developed nosocomial pneumonia. No connection has been noticed between tracheobronchial tree measurements and suggested comorbidities. No anomalies or significant anatomical variations were noticed in any of the patients. Analysis of tracheobronchial tree measurements revealed that the diameters of the tracheobronchial tree and the length of the trachea and the left main bronchus are significantly larger in men than in women. No correlation has been found between tracheobronchial tree measurements with the length of ICU stay. Furthermore, number of hours spent on mechanical ventilation, development of nosocomial pneumonia and final outcome, are not correlated to tracheobronchial tree measurements. Conclusion: No correlation was observed between tracheobronchial tree measurements with the length of ICU stay, nor with the number of hours spent on mechanical ventilation, nor with the development of nosocomial pneumonia and the final outcome.