Objective To investigate the compound cantharis injection TGF-beta1 expression in patients with locally advanced colorectal cancer. Methods Selection of locally advanced colorectal cancer patients admitted in Weifang hospital cancer center， 92 cases were randomly divided into 2 groups， each group of 46 cases respectively. Control group adopts FOLFOX4 chemotherapy treatment， the treatment group on the basis of chemotherapy combined compound cantharis injection， respectively to observe before treatment and after treatment 1， 2， 3， cycle two groups of patients， and serum levels of TGF-beta1 evaluate recent clinical curative effect. Results Two groups in chemotherapy to 1， 2， 3 cycles， two groups of TGF-beta1 level in serum of patients improved， the treatment group were significantly reduced compared with controls， the difference was statistically significant（P<0.05）；Recent clinical efficacy of the treatment group in objective response rate（ORR） and disease control rates are higher than the control group（DCR）， but there was no statistically significant difference（P>0.05）. Conclusion Compound cantharis injection could cut colorectal cancer TGF-beta1 expression level in the organization， and inhibit tumor growth， invasion， the action mechanism may be related to the inhibition of tumor blood vessels and the death of cancer cells， has the good clinical curative effect.