Abstract: Objective To explore the expression of cytokeratin （CK） 19 and mucin （MUC）-1 mRNA in the peripheral blood of patients with colorectal cancer （CRC） and their relationship with clinicopathological parameters. Methods The levels of CK19 and MUC-1 were measured by nested reverse transcription-polymerase chain reaction （RT-PCR） in the peripheral blood of 20 healthy human volunteers （Healthy group）， 20 patients with benign colorectal adenomas （Benign disease group） and 90 patients with CRC （CRC group）. The correlations between levels of CK19 and MUC-1 mRNA and clinicopathological parameters of CRC （Dukes stage， differentiation， distant metastasis and histological type） were analyzed. Results The positive rate of CK19 mRNA was 58.9％ （53／90） of CRC group， higher than 0 of Healthy group and 5.0％ （1／20） of Benign disease group with significant difference （P＜0.05）.The positive rates of MUC-1 mRNA were 52.2％（47／90）， 60.0％（12／20） and 50.0％（10／20） for CRC group， Healthy group and Benign disease group with no significant difference （P＞0.05）. No significant differences were observed between Healthy group and Benign disease group on positive rates of CK19 mRNA and MUC-1mRNA. The positive rates of CK19 mRNA and MUC-1 mRNA were related with Dukes stage， differentiation and distant metastasis， and non-related with histological type （P＜0.05）. Conclusion The positive rate of CK19 mRNA in CRC increased， and CK19 and MUC-1 mRNA related with the Dukes stage， differentiation and distant metastasis， which may play an important role in the development of CRC.