Asthma and obesity remain two of the fastest growing and most pervasive public health problems in developing countries. Obesity appear to increase the risk of asthma.both disorder may share common genetic ,enviromental causes. We studied the asthmatic patients and calculate BMI of patient and study the relation between BMI and eosinophilia,pulmonary function tests varities. Eosinophilia is present in 31 cases (72.09%) but it absent in 12 cases (27.9%). p-value =0.290 whish is insignificant. Restrictive response of the patients which are 21 patients the number of mild restrictive pattern 5 patients (23.8%), number of moderate restrictive are 13 patients (61.9%), number of severe restrictive are 3 (14.3%) p-value = 0.146 which insignificant. Ostructive response are present in (11)patient 6 of them are . mild obstructive (54.5%) and 4 patient are moderate obstructive (36.4%) and 1 patient is severe obstructive in (9.1%) p- value is 0.420 which is insiginificant. Asthma and obesity, control of one of both give better chance to the other, for example weight reduction improve the severity of asthma