Background: In bronchiolitis, children under the age of two experience cough, dyspnea and wheezing, following a viral upper respiratory infection. Frequently recurrent bronchiolitis in infants with atopic background is the best example of asthma-prone viral-induced wheeze. In bronchiolitis management, inhaled hypertonic saline is the subject of debate among pediatricians and researchers. Nebulized hypertonic saline acts by increasing fluidity of airway surface liquid. Bronchospasm is a theoretical risk for inhaled hypertonic saline when used without adjunctive bronchodilators.   Objective: To compare the response to nebulized hypertonic saline plus B 2 agonists, with nebulized isotonic saline plus B 2 agonists, in asthma-prone and non-asthma-prone bronchiolitis patients. Patients and methods: This study was a randomized double blind controlled trial, which was carried out at Pulmonology Unit, Pediatric Department, Zagazig University Children Hospital. The study was conducted on 104 infants with acute viral bronchiolitis of mild to moderate severity. They were divided into two groups 52 in each group. Group 1: Asthma-prone patients and group 2, which included non-asthma-prone patients. Patients were randomly assigned to receive inhalation of 0.3 mg/kg salbutamol added to 5 ml of either normal saline 0.9% or hypertonic saline 3%. Within each group the number of patients receiving hypertonic or isotonic saline inhalation was equal to 26. Results: Nebulized hypertonic saline salbutamol mixture resulted in better improvement of the studied asthma-prone and non-asthma prone bronchiolitis patients. Hypertonic saline decreased case severity and days of hospital stay. Conclusion: Nebulized hypertonic saline shortened the days of hospital admission and improved the respiratory distress in mild to moderate bronchiolitis. Nebulized hypertonic saline is equally effective in asthma-prone and non-asthma-prone patients and its beneficial effect outweighs its theoretical broncho-constrictive effect.