In this study, the observation of tumor volume changes showed that the 5-fluorouracil extended-release implant perineural implant high and low dose groups showed significant volume reduction at 12 days after administration compared with the 5-fluorouracil injection local injection and control groups, and the results were statistically different; while there was no statistical difference between the 5-fluorouracil injection local injection high and low dose groups compared with the control group; indicating that the 5-fluorouracil extended-release implant topical application had a significant inhibitory effect on colorectal cancer transplantation tumors. The tumor inhibition rate of 5-fluorouracil extended-release implantation not only had a significant tumor inhibition effect, but also the higher the dose administered, the more obvious the inhibition effect was, showing a dose-effect relationship. 72% tumor inhibition rate was achieved in the high-dose group and 51% in the low-dose group of 5-fluorouracil extended-release implantation, which was significantly higher than that of 5-fluorouracil injection. In this study, the mortality rate of animals in the high-dose group of 5-fluorouracil extended-release implant topical application was 10%, and there was no mortality in the low-dose group; the mortality rate in the high-dose group of 5-fluorouracil injection topical application reached 40%, and the mortality rate in the low-dose group also reached 10%, suggesting that 5-fluorouracil extended-release implant topical application can reduce the toxic side effects of the drug. In this study, we found that all animals showed weight loss after drug administration, but the weight reduction in the high-dose group of 5-fluorouracil extended-release implant was lower than that in the high-dose group of 5-fluorouracil injection topical injection, and there was no statistical difference between the weight of the groups at the end of the experiment. The results of this study suggest that perineural implantation of 5-fluorouracil extended-release implant has a reliable therapeutic effect on colorectal cancer transplantation tumors, and the preparation is able to destroy residual tumor lesions after colorectal cancer surgery by bed implantation, which has certain clinical application value.