Liver fibrogenesis involves the synthesis of collagen fibrils and proteoglycans by various types of liver cells, including Ito cells, transitional cells, myofibroblasts and hepatocytes. Synthesis of collagen fibrils follows a complex metabolic pathway with intermediate products such as type III procollagen (III-PC). Serum levels of III-PC may reflect the activity of the fibrogenetic process. We analysed the relationship between the serum levels of III-PC (N-terminal peptide) and diverse clinical, biochemical and histological parameters of 77 alcoholic patients (27 cirrhotics), comparing them with those of 15 age- and sex-matched controls. A highly significant difference was obtained between controls and patients (P < 0.0001), but no differences were observed between cirrhotics and non-cirrhotics. Serum III-PC significantly correlated with clinical and biochemical data of liver function derangement (prothrombin activity, serum albumin, bilirubin, gynecomastia, ascites, encephalopathy, edema, splenomegaly); with the duration of ethanol addiction and with MCV. Sixty patients were followed up for a period ranging between 3 and 1056 days (mean = 356 days); 9 of them died. Patients with III-PC levels above 38 ng/ml had a significantly higher mortality (P = 0.006) than those with levels under 38 (log rank test). Thus, serum III-PC may be a useful tool in the clinical evaluation and prognostic assessment of patients with chronic alcoholic liver disease. © 1990.