The study was designed to determine the ameliorative potential of quercetin and catechin against the toxicity induced by co-exposure to Mancozeb (MZ) and arsenic in Wistar rats. Sixty-adult male Wistar rats were randomly divided into 10 groups (n=6). Group I served as control and group II was exposed to MZ [800 mg/kg, PO (per OS)]. Groups III, IV, and V were given drinking water containing sodium arsenite at the rate of 10, 50, and 100 ppb, respectively, for 28 days. Groups VI, VII, and VIII were treated with sodium arsenite in drinking water at 10, 50, and 100 ppb, respectively, along with MZ (800 mg/kg) for 28 days. Groups IX and X were given drinking water mixed with sodium arsenite at 100 ppb, MZ at 800 mg/kg, and quercetin (50 mg/kg) and catechin (50 mg/ kg), respectively. Co-exposure to the toxicants (MZ and arsenic) significantly (P<0.05) aggravated the oxidative stress-induced alterations and the histopathological changes induced by individual toxicants. Supplementation of quercetin or catechin markedly attenuated the variations in nitric oxide levels and oxidative biomarkers in blood and the brain and shielded the histomorphology of the brain against oxidative damage.