Mancozeb (Mz) is one of the most widely used pesticides that has been reported to cause adverse human health risks. WhiteNelumbo nucifera(N. nucifera) petals have therapeutic properties to prevent toxicity. Hence, this study attempted to determine the effects ofN. nuciferaextract on hepatotoxicity and oxidative stress in mancozeb-treated rats. Seventy-two male rats were divided into nine groups and designed with a control;N. nuciferaextract was administered at the doses of 0.55, 1.1, and 2.2 mg/kg bw/day, Mz was administered at 500 mg/kg bw/day, and the co-treatment groups (N. nuciferaand Mz) were administered 0.55, 1.1, and 2.2 mg/kg bw/day ofN. nuciferafollowed by administering Mz 500 mg/kg bw/day daily for 30 days. The results showed that all doses ofN. nuciferaextract did not induce hepatic toxicity and could suppress the toxicity of mancozeb by increasing body weight gain and decreasing relative liver weight, lobular inflammation, and total injury score. The combination treatment also decreased the molecular markers of oxidative stress (2-hydroxybutyric acid, 4-hydroxynonenal, l-tyrosine, pentosidine, and N6-carboxymethyllysine). Furthermore, the reduced glutathione and oxidized glutathione contents were adjusted close to the normal level. Therefore,N. nuciferaextract is a natural antioxidant supplement that could decrease the toxicity of mancozeb and can be safely consumed.