Pesticide chemicals may induce oxidative stress leading to generation of free radicals and alterations in antioxidants or oxygen free radical (OFR) scavenging enzymes. Hence, the effect of subchronic malathion (O,O-dimethyl-S-1,2, bis ethoxy carbonyl ethyl phosphorodithioate) exposure was evaluated on lipid peroxidation, glutathione and related enzymes and OFR scavenging enzymes in albino rats. Administration of malathion (20 ppm) for 4 weeks increased the malondialdehyde (MDA) levels in serum, activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) in erythrocytes and glutathione reductase (GR) and glutathione S-transferase (GST) in serum. However, it decreased the glutathione (GSH) level in whole blood. Concomitant dietary feeding of Zingiber officinales Rosc (ginger 1%, w/w) significantly attenuated malathion induced lipid peroxidation and oxidative stress in these rats. These results indicate the possible involvement of free radicals in organophosphate-induced toxicity and highlight the protective action of ginger, an indigenous medicinal plant product.