Difenacoum is the second generation anticoagulant rodenticidehydroxycoumarin compounds (SGARs) that are more toxic compared to the first one. It is used as pesticides to control harmful rodents. The present work was piloted to evaluate the histological and ultrastructure effects after difenacoum inducement in the liver of albino rat. Oral administration of the two doses (0.25mg/kg and0.5 mg/kg) for two periods(2days and 4days) of difenacoum induced many histological and ultrastructure alterations in the hepatic tissue. The liver tissue showed congestion of blood vessels, leucocytic infiltrations, compressed sinusoids and enlargement of kupffer cells,necrotic nuclei and cytoplasmic vacuolization of fatty degeneration in the hepatocytes. Moreover, ultrastructure observations revealed shrinkage nuclei with condensation of heterochromatin and lipid droplets,destructedrough endoplasmic reticulum and mitochondria that were ill-differentiated cisternae.The observed alterations were dose and time dependent. Consequently, it is suggested that difenacoum induced vigorous hepatotoxicity concludedin the histological and ultrastructure changesof adult albino rat liver.The resulted severity was dose and time dependent