Pesticides are the substances used to kill pests which adversely affect human health or agricultural yield. They usually alter certain physiological or reproduction cycles of pest’s life finally focusing to get rid of them. In the present study the levels of pseudo cholinesterase (PChE) in 53 organophosphorus (OP)-poisoned cases were obtained from the clinical laboratory. Serum was collected for the determination of malondialdehyde (MDA), ferric reducing ability of plasma (FRAP), glutathione-S-transferase (GST) and total thiols which were estimated spectrophotometrically. The results revealed the significant Correlation of PChE with FRAP, MDA, GST & total thiols, whereas β glucuronidase showed no significant correlation. Correlation of MDA with PChE, FRAP, GST and total thiols was significant, whereas β glucuronidase showed no significant correlation. MDA, used as a conventional biomarker for oxidative damage, showing moderate negative correlation with GST, FRAP and total thiols suggests that the oxidative damage occurred has been counter stroked by antioxidant pool majorly consisting of GST, FRAP and total thiols. There are various studies that support the same. Correlation of PChE with MDA showing highly significant negative correlation gives us evidence that severe oxidative damage (with elevated levels of MDA) occurs in OP poisoning cases due to generation of reactive oxygen species (ROS). The current study concludes that, OP poisoning along with collapsing cholinergic system at neural synapses accounts for the generation of reactive oxygen species which leads to neurological complications coupled with severe multiorgan breakdown.