Abstract: Objective To investigate the expression of human circadianclock genes hClock and hBmal1 in different Dukes stages of colorectal tumors and its correlation with colorectal cancer invasion and metastasis. Methods Using in situ hybridization detection of colorectal tumor and corresponding adjacent tumor tissues to detect hClock and hBmal1 gene mRNA level.Immunohistochemical assay was used to detect the corresponding specimens hClock gene protein product (CLOCK protein) expression. Results In 32 cases of colorectal tumors hClock mRNA positive expression rate was 93.75%(30/32)，medium or strong positive expression rate was 78.13%(25/32)；hBmal1 mRNA positive expression rate was 71.88%(23/32)，medium or strong positive expression rate was 40.63%(13/32).Their medium or strong positive expression was relevant with the staging of Dukes (P<0.05).hClock and hBmal1 gene mRNA weak expressed in positive position of the tumor tissues and corresponding adjacent tissues.CLOCK protein medium or strong positive expression rate was 87.50%(28/32)，the CLOCK protein of tumor adjacent tissues weak positive rate was (30/32) 93.75% (P<0.01). Conclusion hClock and hBmal1 genes are certain relevant with the occurrence and development of colorectal tumor，in the same with their invasions and metastases.