32 asthmatic children out of which 22 males and 10 females with ages ranging between 6 and 8 years presenting to Abu El Reesh Hospital – Cairo University. Our subjects were presenting with intermittent or mild persistent asthma. Each child received 0.1 mg salbutamol inhalation/kg in 4 ml saline for 3 times and O2. The duration in between the inhalations was 20 minutes. For each child, after the accurate history taken and meticulous clinical examination, the following were done:•PEFR•Serum IgE•Serum lactate levels before, immediately after, and 24 hours following salbutamol inhalation therapy•Blood gases analysis before and after salbutamol inhalation therapyOur results concerning lactate revealed:1-Highly significant difference between the pre and post immediate treatment serum lactate levels.2-Highly significant difference between pretreatment and the 24 hour post treatment serum lactate levels.3-The difference between the immediate and the 24 hour post treatment was highly statistically 4-Immediate post treatment serum lactate was significantly higher in patients with severe asthmatic exacerbations than those with moderate asthmatic exacerbations.5-Immediate post treatment serum lactate was significantly higher in patients with mild persistent than those with intermitted asthma.6-Immediate post treatment serum lactate was significantly higher in patients using oral corticosteroids than those non users.And so from our results lactatemia is a common finding during treatment of acute severe asthma in children. However, it is not predictive of bad prognosis or respiratory failure.