BACKGROUND/AIMS There is increasing evidence to show that the presence of raised concentrations of serum C-reactive protein (CRP) is associated with poor survival in patients with colorectal carcinoma. The CRP response with respect to tumor characteristics in colorectal carcinoma was examined to identify factors that might reflect a raised CRP level. METHODOLOGY One hundred and eighty-one patients who underwent elective colorectal resection were identified for inclusion in this study. Eighteen patients with high CRP levels were compared to a control group of 163 patients without high CRP levels, and the correlation between preoperative CRP level and clinicopathological features in operable colorectal carcinoma was investigated. RESULTS The analysis of factors with seeming potential to be associated with CRP levels following colorectal surgery, disclosed that only the depth of tumor invasion, serum albumin and lymphovascular invasion were of statistical significance. Multivariate subgroup analysis of the association between these factors and CRP showed that depth of invasion and albumin were independently associated with CRP. CONCLUSIONS Our results suggest that depth of tumor invasion is associated with an increase in CRP levels. CRP is considered an important indicator of advanced local invasion in operable colorectal surgery, if other inflammatory conditions are excluded.