Abstract: Objective To investigate risk factors associated with peritoneal metastasis in colorectal cancer. Methods Clinicopathological data of 873 patients with colorectal cancer treated at the Nanfang Hospital of Southern Medical University from January 2003 to December 2008 were retrospectively analyzed. The associations between peritoneal metastasis and cliniopathological factors were evaluated by univariate analysis including independent-samples t test and x2 test, and multivariable logistic regression analysis. Results Univariate analysis showed that age(P=0.032), tumor size(P=0.001 ),tumor differentiation (P=0.008), depth of bowel wall invasion ( P=0.000 ), lymph node metastasis ( P=0.000 ),serum carcinoembryonic antigen (CEA) level(P=0.003), and serum carbohydrate antigen 19-9(CA19-9)level (P=0.009) were associated with peritoneal metastasis. On multivariable logistic regression analysis,depth ofbowelwallinvasion, lymph node metastasis, serum CEA level and CA19-9 level remained as significant risk factors (all P<0.05). Conclusion Depth of bowel wall invasion, lymph node metastasis,serum CEA level, and CA19-9 level are risk factors for peritoneal metastasis in colorectal cancer.