Background/Aims: This study was performed to assess the significance of elevated serum tissue inhibitor of metalloproteinases-1 concentration in various liver diseases. Methods: Tissue inhibitor of metalloproteinases-1 levels were measured in patients with various liver diseases, and were compared with serum type III procollagen-N-peptide (P III P), type IV collagen and laminin P-1 levels, as well as with the histology of liver biopsy specimens. Results: Mean tissue inhibitor of metalloproteinases-1 levels were significantly higher in subjects with acute viral hepatitis, cirrhosis, alcoholic hepatitis, and alcoholic cirrhosis than in the control group (p<0.05). Serum tissue inhibitor of metalloproteinases-1 levels in the various liver diseases showed positive correlation with serum type IV collagen, P III P, and laminin P-1 levels. Regarding the relationship between tissue inhibitor of metalloproteinases-1 and liver histology, serum tissue inhibitor of metalloproteinases-1 levels correlated with the degree of hepatic fibrosis and inflammation, such as focal necrosis and cell infiltration. Furthermore, elevated serum tissue inhibitor of metalloproteinases-l levels were especially related to the cell infiltration, focal necrosis, portal fibrosis, and serum type TV collagen level. Conclusions: These findings suggest that the measurement of the serum tissue inhibitor of metalloproteinases-1 level in various liver diseases may be useful to estimate the active hepatic fibrogenesis associated with the active inflammatory stage of the liver injury.