p27 is known as one of the candidate tumor suppressor genes. Although abnormalities including deletion and mutation in this gene are rarely detected, loss of p27 expression has been reported to be correlated with the high degree of malignancy in many human cancers. In the present study, we investigated the status of p27 expression in human pancreatic carcinoma (PC) and assessed the clinicopathologic significance of loss of p27 expression in the development and progression of this malignancy using immunohistochemistry. No nuclear staining for p27 protein existed in 65 (65.7%) of the 99 PC tumors examined. Furthermore, loss of p27 expression was correlated with tumor grade (G1 versus G2 or G3, p < 0.05) or clinical stage (I and II versus III and IV, p < 0.01). The above data suggest that loss of p27 expression is a very common event in PC, and moreover, this alteration might contribute to the progression of this malignant disease.