Abstract: obective Colorectal cancer (CRC) patients are often accompanied by changes of serological such as elevated tumor markers, anemia, and hypoproteinemia which may be associated with a poor prognosis. This study aims to systematically evaluate the relationship between preoperative parameters of routine blood tests and tumor size, metastasis and stage by using a large sample size of patients with CRC. Methods Information of 932 patients with CRC undergoing surgery in tertiary hospital from December 2009 to September 2017 were enrolled, and the routine blood tests data and serum tumor markers in a week before the operation were collected. SPSS software was used to analyze the relationship between systemic inflammation, albumin, CEA, and CA199 and tumor size, lymph node metastasis, distant metastasis, TNM stage, and histopathological grade. Results Among the 932 patients, there were 538 males and 593 rectal cancers cases. The age ranged from 24 to 89 years, with an average age of 61.89±11.98 years and a median age of 63 years. Compared with early T0-2 patients, T3 and T4 patients had higher levels of CEA (P<0.01), CA199 (P<0.01) and neutrophils (P=0.03); whereas lymphocytes (P=0.03) and hemoglobin (P=0.001) decreased. Compared with those in patients without metastasis, patients with lymph node metastasis had elevated CEA (P=0.001) and CA199 (P=0.002) levels. Patients with distant metastasis had higher white blood cells (P=0.014), neutrophils (P=0.001) and CEA (P=0.02) than that of patients without metastasis. ROC curve analysis showed that the sensitivity and specificity of fitted curves of preoperative systemic inflammation, CEA, and CA199 for ≥ T3 stage was 86.5% and 49.1%; the fitted curves of preoperative CEA and CA199 for lymph node metastasis was 67.4% and 56.7%; the fitted curves of preoperative CEA and CA199 for distant metastasis was 88.9% and 24.8%, respectively. Conclusion Preoperative routine blood tests, CEA, CA199 were significantly different among patients in terms of tumor size, lymph node positive, and distant metastasis, TNM stage which are associated with the long-term prognosis of patients with CRC. However, the predictive value and the positive relevance are limited