Invasion of human erythrocytes by malaria parasites causes alterations in antioxidant po-tential of the red cells. The present study was undertaken to investigate the erythrocyte an-tioxidant enzymes like superoxide dismutase(SOD), catalase(CAT) in malaria patients. Oxi-dative stress was estimated by measuring malondialdehyde(MDA) which is a marker for lipid peroxidation. 30 malaria patients were enrolled in this study. They were divided into 2 groups of 15 each with Plasmodium vivax malaria and Plasmodium falciparum malaria. Re-sults were compared with 20 healthy control subjects. Significant decrease(p<0.001) in SOD and CAT and increase in MDA (p<0.001) indicates that there is reduction in antioxidant en-zymes and increased vulnerability to free radical damage in erythrocytes. This study there-fore emphasizes the need for early treatment of malaria patients to reduce the red cell dam-age.