Organophosphorus (OP) poisoning is a worldwide public health problem. Assessment of oxidative stress and antioxidant status using many biochemical parameters has become a notable research work. In this view, the serum nitric oxide (NO) levels are checked as an indicator of oxidative stress. Serum levels of Vitamin E, Vitamin C, glutathione reductase and glutathione peroxidase are checked as a marker of antioxidant property. Correlation of oxidative stress biomarker NO with other antioxidant parameters such as Vitamin E, Vitamin C, glutathione reductase and glutathione peroxidase is done in the study. The results show that vitamin C and vitamin E decreased in cases of organophosphorus poisoning whereas NO, glutathione reductase and glutathione peroxidase increased compared to controls, with statistical significance p < 0.0001. Nitric oxide shows a negative correlation between vitamin C and glutathione peroxidase and shows a positive correlation between vitamin E and glutathione reductase. But the positive correlation between vitamin E and glutathione reductase is statistically insignificant.