Background: Acetaminophen (APAP) hepatotoxicity is a highly prevalent drug used for the treatment of pain. Allium hooshidaryae is widely used as herbal medicine in western Iran. Objectives: In this study, we investigated the protective eff ects of A. hooshidaryae methanolic extract (AhME) on liver damage induced by APAP. Methods: Rats were divided into six groups. Groups 1 (negative control) and 2 (positive control) received normal saline; groups 3 received 200 mg/kg of AhME, and groups 4-6 received AhME at the doses of 50, 100, and 200 mg/kg once daily, by gavage, respectively. After the 14 days, except for groups 1 and 3, the other groups received 2 g/kg of APAP. After 48 hours, hepatic tissue and blood sample were taken for histopathology and biochemical experiments. Results: APAP induced a notable increase in serum levels of aspartate transaminase (AST, P < 0. 001), alanine transaminase (ALT, P < 0. 001), alkaline phosphatase (ALP, P < 0. 001), lactate dehydrogenase (LDH, P < 0. 01), nitric oxide (NO, P < 0. 001), and lipid peroxidation (LPO, P < 0. 001) levels in hepatic tissue. It also signifi cantly reduced the level of total antioxidant capacity (TAC), total thiol groups (TTGs) as well as glutathione contents (GSH) in hepatic tissue (For all P < 0. 001). Following the use of AhME, a noteworthy improvement was observed in hepatic serum enzymes and oxidant/antioxidant parameters in liver tissue. Conclusions: This study demonstrated that AhME prevents APAP-induced hepatotoxicity through improvement in the hepatic antioxidant status.