Introduction and research objective: Acute lower respiratory tract infections are one of the leading causes of morbidity and mortality in children. Respiratory physiotherapy as a part of the physiotherapy process plays an important role in the treatment of children with respiratory diseases. The aim of this study is to examine the impact of respiratory physiotherapy on vital signs in children hospitalized for acute respiratory infection of the lower respiratory tract. Participants and methods: The subjects of the research are children of preschool age (0-6 years) who were hospitalized due to acute respiratory infections of the lower respiratory tract and who were prescribed respiratory physiotherapy as part of the therapeutic protocol. Respiratory physiotherapy procedures included positional drainage, manual percussion, chest vibration in the expiratory phase and active expectoration/aspiration. Vital signs (peripheral oxygen saturation (SpO2), respiratory rate, heart rate) were measured before therapy, immediately after therapy, 5 minutes and 10 minutes after therapy. Results: The research sample consisted of a total of 30 subjects, of which 12 were male and 18 were female. Respiratory physiotherapy procedures showed a statistically significant decrease in heart rate, breathing frequency and an increase in SpO2 in the observed 10-minute interval. None of the observed independent variables (gender, age, frequency of infections) had a significant impact on the differences in vital signs before and 10 minutes after therapy. Conclusion: Respiratory physiotherapy has a positive effect on vital signs in children with acute respiratory infections, regardless of gender, age and frequency of infections. Further research should include a larger number of subjects and longer follow-up to better understand the long-term effects of the therapy.