Mercury (II) is an important factor in hepatotoxicity that can enter the body through marine diets and amalgams. In the present study, the protective effect of the Eriobotrya japonica flower extract (EJFE) on HgCl2-induced hepatotoxicity was investigated. Five mg/kg of mercuric chloride in drinking water was given to rats either with saline or EJFE (100 and 200 mg/kg as intraperitoneal (IP)) for 30 d. The mercury levels in different groups of liver tissues of the rats were measured with flameless atomic absorption spectroscopy (F-AAS). Also, mercury accumulation in the liver of the rats was modeled by using a parallel chemical kinetic model. The results showed that HgCl2-induced oxidative damage led to a significant decrease in glutathione (GSH) and the total antioxidant capacity (TAC) levels, and to a significant increase in lipid peroxidation level. Accumulated mercury was 14.47% more in the livers of the stress groups than in those of the control groups (P<0.001), whereas the amount of Hg was adjusted to 13.49% and 13.93% in groups treated with 100 and 200 mg/kg of EJFE respectively, as compared with stress groups (P<0.001). HPLC analysis of EJFE revealed that hesperetin and gallic acid are the major antioxidants in EJFE. Results demonstrate that flowers of the Eriobotrya japonica cause a significant protection against HgCl2 induced hepatotoxicity in all diagnostic parameters by strengthening the antioxidant defense mechanisms and they may have a therapeutic function in free radical mediated diseases.