Abstract: To probe the role of ras oncogene p21 product, IGF-Ⅱ and proliferating cell nuclear antigen (PCNA) in the development of cirrhotic nodules, liver cell dysplasia and hepatocellular carcinoma (HCC) . S-P immunohistochemical technique was used to analyze the expression of p21, IGF-Ⅱ, PCNA and HBsAg in 50 cases of liver cirrhosis without HCC, 28 cases of paracancerous liver cirrhotic tissues, and 22 HCC cases. The positive rates for p21 in cirrhosis with or without HCC, and HCC tissue were 92 86%, 68%, 54 55%, respectively. The positive rates for IGF-Ⅱ in cirrhosis with or without HCC, and HCC tissue were 75%, 74%, 36 36%, respectively. The positive rates for p21, IGF-Ⅱ and PCNA in cirrhotic nodules with LCD or with HBsAg infection which were significantly higher than those without LCD or without HBsAg infection ( P <0 05) . The incidence of p21 expression in hepatocytes was significantly higher in IGF-Ⅱ and PCNA in positive cases than in negative ones ( P <0 01) . The expression levels of p21, IGF-Ⅱ and PCNA in liver cirrhosis are related to HBV infection. They may play a synergetic role in transforming liver cells into cancer. LCD are precancerous cells which have the ability to initiate neoplastic growth and present a high risk of development of HCC, especially when it was combined with HBV infection and the overexpressions of p21, IGF-Ⅱ and PCNA.