Psoriasis is a chronic inflammatory skin disease characterized by the immune systemrnactivation in which the genetic and environmental factors are involved that trigger therndevelopment of skin lesions. Reactive oxygen species produced as a result of skinrninflammation may cause disorders of the antioxidant defense systems and increasedrnoxidative stress in psoriasis which was proposed to have to have a consequent function inrnpsoriasis.rnAim of the study: The presented research work was planned to evaluate oxidative stress byrnmeasuring Total Oxidant Capacity, Total Anti-oxidant capacity and Oxidative Stress Indexrnin psoriatic patients.rnMethods: A comparative cross-sectional study was undertaken with 45 clinically diagnosedrnpsoriatic patients without any drug therapy and 45 age-sexes matched healthy controls. Thernseverity of psoriasis was determined by Psoriasis area severity index. Out of total 45rnPsoriasis patients, 22 were mild, 15 moderate and remaining 8 were severe psoriaticrnpatients. Levels of Total Oxidant Capacity, Total Anti-oxidant Capacity and OxidativernStress Index were measured in patients and controls.rnResults: The present study showed significantly (p