During 1,414,144 person-years of follow-up, cholangiocarcinoma occurred among 222 patients with use of DPP4 inhibitors (incidence rate, 26 per 100,000 patient-years) and among 128 patients with use of sulfonylureas (incidence rate, 23 per 100,000 patient-years). Here, DPP4 is linked to cholangiocarcinoma.