In this study, we extensively investigated the role of DPYD in pancreatic cancer using DPYD‐overexpressing pancreatic cancer cells and evaluated the therapeutic effect of a combination treatment with 5‐FU and Lut on pancreatic cancer using xenograft models and Pdx‐Cre; LSL‐KrasG12D/+; Trp53flox/flox (KPPC) mice. Here, DPYD is linked to familial pancreatic carcinoma.