To study the relationship between serum level of type Ⅲ procollagen, N - terminal procollagen Ⅲ peptide and hepatic fibrosis and their clinical value, PCⅢ, PⅢNP were tested by RIA in 114 serum samples of chronic hepatitis patients. These patients were also examined by liver biopsy, and performed by pathomorphology. Compare PCⅢ and PⅢ NP with hepatic fibrosis indexes according to inflammation grade, fibrosis staging and chronic hepatitis degree. The re- sults show that PCⅢ and PⅢ NP have significant relationship to inflammation grade, fibrosis staging and the degree of chronic hepatitis (P 0. 01). The coefficient correlation of the results of histopathological examinations indexes to PCⅢ and to PⅢ NP are 0 .446, 0. 412, 0. 343;0. 463, 0. 403, 0. 308, respectively. And PⅢ NP is more sensitive than PCⅢ in determining fibrosis staging and the degree of chronic hepatitis (P 0. 01). Thus, serum levels of PCⅢ and PⅢ NP are fairiy well correlated with the inflammation grade, fibrosis staging and chronic hepatitis degree. And PⅢ NP is more sensitive than PCⅢ in eary hepatic fibrosis.