To study the mechanism of p16,Cyclin D1 and CDK4 and their relationship with pancreatic carcinoma, their expressions were examined by immunchistochemistry methods. Results: overpression of Cyclin D1 and CDK4 was revealed in these samples and p16 was undertectable. There was a negitive correlation between p16 and Cyclin D1 (Ｐ＜0.05), and a positive relation between Cyclin D1 and CDK4 (Ｐ＜0.05). The results indicate that abnormality of p16, Cyclin D1 and CDK4 may be involved in the molecular mechanism of pancreatic carcinoma, p16 lower expression and Cyclin D1 over expression may coexit in the development of pancreatic carcinoma.