Abstract: Objective : To investigate the expression and clinicopathologic characteristics of p27 and Skp2 proteins in colorectal carcinomas and to explore the relationship between p27 and Skp2 in colorectal carcinomas. Methods : The expression of p27 and Skp2 proteins were determined using immunohistochemical S-P method in 30 cases with colorectal carcinomas and 18 with normal colorectal tissues. Results : The average positive rate of p27 protein in normal colorectal tissues was 55.2%, which was significantly higher than that in colorectal carcinomas (27.5%) (P<0.05). The p27 expression in colorectal carcinomas was significantly associated with Dukes stage, regional lymph node status and histological grade (P<0.05). The average positive rate of Skp2 protein in colorectal carcinomas was 9.5%, which was higher than that in normal colorectal tissues (1.8%) (P<0.05). The Skp2 expression was associated with histology in colorectal carcinomas (P<0.05). However, there was no correlation between the Skp2 expression and age, sex, nodal involvement and Dukes stage (P<0.05). There was a reverse relationship between the p27 expression and Skp2 expression in colorectal carcinomas (r=-0.806, P0.01). Conclusion : The Skp2 protein was involved in the degradation of p27 protein. Skp2 was a potential oncogenic gene and associated with the development of colorectal carcinoma. Skp2 could be a promising target for future cancer therapy strategies.