Asthma is a chronic disorder of the airways with underlying inflammation and oxidative stress. Malondialdehyde (MDA) - the lipid peroxidation product- level increases in inflammatory diseases and used as a common oxidative stress marker. Albumin and bilirubin are components of antioxidant defense system. The aim of this study are, Evaluating oxidative stress as a component of asthma process by measuring MDA (as an oxidative marker), albumin and bilirubin (as biomarkers of antioxidant defense system) in asthmatic patients. Thirty seven asthmatic patients (20