There is inconclusive evidence on the role of nebulized magnesium sulphate (MgSO4) in the management of acute asthma in paediatric population. Whether the use of nebulized salbutamol with or without MgSO4 in the management of acute asthma results in clinically significant improvement in lung function in Indian children? The primary outcome measure was to assess improvements in peak expiratory flow rate (PEFR), heart rate, respiratory rate and SpO2. This was a single centre; prospective double-blind randomized control trial conducted in paediatric intensive care unit of a tertiary care centre. Ninety children of 6-14 years with acute exacerbations of bronchial asthma were enrolled to receive either inhaled magnesium sulphate (95 mg) with salbutamol (5 mg) or inhaled salbutamol (5 mg) alone. All patients got three nebulizations done during the first hour at 20 min intervals, two nebulizations during the second hour at 30 min intervals, hourly for the next 2 h and then at 24 and 48 h. Eighty-five patients were finally analysed as per protocol analysis. The trial showed that PEFR increased gradually in both groups over the study duration, but it was statistically not significant. Heart rate decreased significantly in both groups over the study duration. Respiratory rate decreased significantly between the groups at 24 and 48 h only. SpO2 improved too in both groups but was not significant statistically. The addition of nebulized MgSO4 to salbutamol does not seem to result in improvement in lung function in the management of acute asthma in Indian children.