Objective To study the relationship between blood metastasis of colorectal cancer and cancer metastasis related factors.MethodsCK20 mRNA in peripheral blood was investigated by reverse transcription polymerase chain reaction (RTPCR) and proteins of CD44v6 and p53 in cancer tissues were examined by immunohistochemical in 50 cases of colorectal neoplasm. ResultsThe results showed that the positive rates of peripheral blood micrometastasis of colorectal cancer were 68%. It escalated along with the rising of the Dukes stage, the rates in Dukes C and D stage were significantly higher than that in Dukes A and B stage. The positive rates of CD44v6,p53 expression in colorectal cancer were 74% and 62% respectively. The positive rates of CD44v6 and p53 in Dukes A and B stage were significantly lower than those in Dukes C and D stage,in peripheral blood and colorectal cancer micrometastasispositive group were significantly higher than that in the micrometastasisnegative group. CK20 mRNA was significantly correlated with expressions of CD44v6 and p53 in cancer tissues. Conclusion The detection of CK20 mRNA in blood before operation and after operation examination of CD44v6 and p53 in cancer tissues are helpful for prediction of blood metastasis of colorectal neoplasm and postoperative treatment.