Objective To study the protective effects of fucoidan from Laminaria japonica on CCl_4-induced acute liver injury in mice.Methods Fifty mice were allocated into control group,model group,bifendate group,low and high dosage of fucoidan group randomly.The mice were treat with bifendate(100mg?kg~(-1)) or fucoidan(200,100mg?kg~(-1)) for 10 days. Then 10%CCl_4(10mL?kg~(-1)) was given to mice by intraperitoneal injection.The activities of serum ALT,AST,ALP and BIL were determined,the body weight and liver weight were measured,as well as the pathological changes of the liver were observed in all groups.Results fucoidan(200mg?kg~(-1)) could significantly lower the ALT,AST BIL in serum and the liver index of mice,improve the liver histology.Conclution fucoidan can protect the liver against damage induced by CCl_4 in mice.