Abstract: Asthma is one of the chronic respiratory diseases in children. Asthma is presented as the acute periods combined with the remission periods. Asthma exacerbation is induced by different triggers, therefore the response of peripheral blood maybe also different. Children admitted to hospitals by asthma attack often suffer from moderate or severe asthma. The aim of this study was to evaluate the correlation between peripheral blood cells and the severity of asthma attacks in children. This is a discripitive study in 146 chidren less than 15 years of age which required treatment at hospital due to asthma attacks. The results showed that children admitted to hospital mostly suffer from moderate or severe asthma attacks (99.32 percent). In acute periods, 62.33 percent of children had an increase in the white blood cells, 29.5 percent of them were increased blood eosinophils and 71.92 percent of them were increased in blood neutrophils. The risk of severe asthma attack was 2.5 times higher in children with increased neutrophils compared with children without increased neutrophils (OR= 2.46
95 percent
CI:1.12-7.22). Conclusion: the responses of peripheral blood cells are significant correlated with the severity of asthma attacks.