Liver fibrosis inhibitors containing cysteine (may be in the form of a salt) wherein cysteine is contained as a sole active ingredient for inhibiting liver fibrosis and the daily dose or intake of cysteine is at least 200 mg, expressed in terms of free compound, in case of oral administration or oral intake. These inhibitors can be taken in the form of drugs or foods or drinks. They are efficacious for liver diseases, in particular, cirrhosis such as compensated cirrhosis. These inhibitors are usable not only as drugs for liver diseases but also as foods and drinks for ameliorating and sustaining liver functions such as foods with health claims, food for patients, etc.
