Psoriasis is a chronic inflammatory skin disease characterized by the immune system activation due to genetic and environmental factors that leads to the development of skin lesions. Reactive oxygen species produced as a result of skin inflammation may cause disorders of the antioxidant defense systems and increased oxidative stress in psoriasis which was proposed to have a consequent function in psoriasis. The study was planned to evaluate oxidative stress by measuring Total Oxidant Capacity, Total Anti-oxidant capacity and Oxidative Stress Index in psoriatic patients. Methodology: A comparative cross-sectional study design was used. A total of 90 participants between age of 18-65 years comprising 45 newly diagnosed psoriatic patients and 45 sex and age matched control groups were enrolled in the study. Result: The present study showed significantly increased levels of serum Total Oxidant Capacity (p<0.001) as well as Oxidative Stress Index (p<0.001) in psoriasis patients as compared to controls and positively correlated with severity and duration of the disease. Total Antioxidant capacity levels were significantly (p<0.001) lower in patients than in controls and negatively correlated with severity and duration of the disease. Conclusion: These results provide evidences regarding the role of increased reactive oxygen species with decreased antioxidant activity in psoriatic patients.