In this study, AQP5 overexpression plasmid was transfected into human colorectal cancer cell lines RKO and HCT116, and the effects of AQP5 combined with 5-FU on the proliferation and apoptosis of colorectal cancer cells and the underlying mechanism were investigated by western blotting, MTT assay and flow cytometry. This evidence concerns the gene AQP5 and colorectal cancer.