Background: Organophosphorus insecticides are well known to induce hepatotoxicity. One among this is chlorpyrifos (CPF), which is an insecticide inducing various toxicities including in liver. Objective: This investigation focused on CPF-induced oxidative damage in rat hepatocytes primary culture and the protective effect of Cactus cladode aqueous extract. Materials and Methods: Hepatocytes were treated with CPF (50, 75, and 150 μM) and cactus aqueous extract. On treatment for 48 h, mortality within these cells was determined by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide test, reactive oxygen species (ROS) levels were measured by H2DCFDA test. Furthermore, heat shock protein 70 (HSP70) and CYP1A1/2 levels were determined using western blot analysis. Annexin V and 4',6-diamidino-2-phenylindole analysis was run to determine the level of cell death and cytoprotection exerted by CPF and extracts, respectively. Results: The results showed that CPF increases the levels of H2O2 and HSP70 and induces CYP1A1/2 and mortality within these cells. In the other side of this study, the co-treatment of these cells with CPF and Cactus cladode aqueous extract showed a recovery of these parameters. It also has been found that the Cactus cladode aqueous extract has the potential to do cytoprotective effect by preventing necrosis induced by CPF. Conclusion: Taken together, these findings suggest that the toxicity exerted by CPF in hepatocytes are involved with the generation of ROS and the regulation of well-controlled programmed cell death, which could be well protected by the Cactus cladode extract pretreatment.