Abstract: Objective: The aims of the present study were to determine the expression of transformation growth factor-β₁ (TGF-β₁) mRNA and TGF-β₁protein in the peripheral blood and its relation to serum levels of procollagen type Ⅲ N terminal peptide (PⅢP) in the patients with cirrhosis. Methods: Peripheral blood samples were obtained from 50 patients with cirrhosis and 8 normal healthy volunteers. Total RNA was extracted from PBMC and TGF-β₁mRNA was amplified from total RNA by nested RT PCR. Serum levels of TGF-β₁and PⅢP were determined. Results: TGF-β₁mRNA could be detected in the peripheral blood mononuclear (PBMC) with high positive rate and serum levels of TGF-β₁and PⅢP were significantly higher than controls.Conclusion: These results confirm the increased expression of TGF-β₁and the positive correlation between TGF-β₁and PⅢP in the patients with cirrhosis. And our results support the suggestion that TGF-β₁may be a significant factor in the increased collagen systhesis of human fibrosis.