Bisphenol A (or BPA) is a toxic endocrine disruptor that is emitted into the environment as a result of industrial manufacturing methods. In this research, we focused on investigating the protective effects of Nigella sativa oil (NSO) on the liver in rats treated with hepatotoxic BPA. For this purpose, 30 Wistar Albino rats were divided into 4 groups: Control (1 ml olive oil); NSO (5 ml/kg NSO); BPA (100mg/kg); BPA+ NSO (100 mg/kg BPA + 5 ml/kg NSO). All applications were done by oral gavage. At the end of the 30-day study period, blood samples of the anesthetized rats were collected and euthanized under appropriate conditions. After removing the serum of the collected blood samples, alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and gamma glutamyl transferase (GGT) levels, which have a key role in liver toxicity, were measured. At the same time, liver samples that were dissected and removed from the cadaver were fixed in 10% formaldehyde solution for histopathological examination and scoring, and hematoxylin - eosin staining were performed. BPA caused degeneration and necrosis in hepatocytes, Kuffper activation, bile duct hyperplasia, congestion, and hepatic cord dissociation, causing serious increases in total liver lesion scores. In parallel, BPA-induced increases were detected in ALT, AST, ALP, and GGT levels. The histological architecture and liver function tests were significantly improved with the addition of NSO to the diet. These findings provided that NSO has a hepatoprotective effect by improving BPA-induced liver damage.