AbstractAsthma is one of the most common chronic conditions affecting both children and adults. It is considered a chronic inflammatory disorder of the airways in which many cells and cellular elements play a role. This chronic inflammation causes an associated increase in airway hyper-responsiveness that leads to recurrent episodes of wheezing, breathlessness, chest tightness and cough. This work was carried out on 90 subjects (60 of them asthmatic patients and 30 healthy as control). Patients were diagnosed, treated and followed up in chest unit in Pediatric Department, Zagazig university.Two groups were included in this study:Group (1): 60 asthmatic patients in acute attack (5-15 years in age)Group (2): 30 healthy children as controlAll studied groups were subjected to:• Complete history taking, full clinical examination and laboratory investigations included.• Complete blood picture, chest –x ray, serum T.N.F-α by ELISA & serum IgE by ELISAIn our study, no statistical significant difference between studied groups as regard of sex.As regard to our study their was no statistical significant difference between studied group as regard to the age which range from 5-15 years which reveal characteristics of studied group as regard to age.In our study, their was statistical significant higher level of HB {60 cases (27 non-allergic&33 allergic), 30 control} with mean range from {(10.47±1.39), (10.54±1.53) & (12.48±1.05)} respectively, Neutrophils {60 cases (27 non-allergic&33 allergic), 30 control} with mean range from {(35.44±5.35), (58.54±6.10) & (25.43±5.62)} respectively, Eosinophils{60 cases (27 non-allergic&33 allergic), 30 control} with mean range from {(5.66±2.20), (15.06±3.54) & (2.66±2.84)} respectively & Platelets {60 cases (27 non-allergic&33 allergic), 30 control} with mean range from {(457±141.11), (469.48±118.90) & (391.76±103.48)} respectively in the asthmatic patients compared to the control groups & shows no statistical significant difference between studied groups as regard other criteria as R.B.Cs, W.B.Cs &Lymphocyte and no statistical significant difference between monocyte and asthma.