Methyl parathion (MP) is an organophosphorus pesticide that can induce hepatotoxicity in living organisms. Although many plant extracts have been utilized againts MP induced liver injury, it has not yet known whether Nigella sativa L. extract (NSE) has protective effects or not. We aim to investigate the hepatoprotective effect of NSE through the oxidative stress and anti-inflammatory pathways. A total of 28 rats were divided into 4 groups; control, MP, NSE and MP + NSE. We measured liver MDA level and antioxidant parameters, hepatic function enzyme, plasma cytokine levels, liver MPO activity, liver iNOS and COX-2 mRNA levels and MAPK/NF-kappa b protein levels. Our data showed that MP increased hepatic function tests, liver MDA level and MPO activity, plasma proinflammatory cytokines, liver iNOS and COX-2 rnRNA and MAPKs protein levels and decreased antioxidant parameters, antiinflammatory cytokine and liver NF-kappa b protein levels. NSE decreased hepatic function tests, liver MDA level and MPO activity, plasma proinflammatory cytokines, liver iNOS and COX-2 mRNA and MAPKs protein levels and increased antioxidant parameters, anti-inflammatory cytokine and liver NF-kappa b protein levels in the MP treated rats. These results suggested the antiinflammatory and antioxidative function of NSE in MP induced liver injury.