In this study serum magnesium, Zinc, and Glutathione levels were estimated in 54 asthmatic patients and compared with 30 healthy controls. Serum magnesium , and serum zinc were -determined by using Atomic Absorption Spectrophotometer. While serum glutathione was determined by spectrophotometric analysis. All the asthmatic patients had their Pulmonary function test, and the parameters of this test have been studied as the effectors on the levels of Mg,Zn,and GSH. The asthmatic patients were divided into four groups according to the interpretation of the pulmonary function test: severe expiratory flow limitation , moderate expiratory flow limitation, slight expiratory flow limitation, , and normal lung values . It was found that the means of Mg in severe cases of asthmatic patients were lower than healthy while the other cases showed no differences, as compared with control. As for the means of serum Zn the slight cases of asthmatic patients •higher than healthy control, while the other cases showed no differences as compared with healthy control. The of serum GSH in serum severe cases of asthmatic patients were lower than the healthy control while the other cases showed compared with healthy control. Also, no significant correlation was found between serum Mg, m Zn, and serum GSH levels of the asthmatic patient and their parameters of pulmonary function test (PFT).