Abstract: Perihilar cholangiocarcinoma is the common type of malignant tumor in the biliary tract. The diagnosis and treatment of perihilar cholangiocarcinoma involve multiple aspects such as epidemiology, clinical diagnosis, imaging examination, clinical classification and staging, pathology, resectability evaluation, perioperative management, surgical planning, systematic treat-ment, and follow-up monitoring, which make it as one of the difficult and technically demanding fields in hepatobiliary surgery. In order to guide the more standardized, safe, and effective treatment of hilar cholangiocarcinoma in China, the Society for Hepato‑pancreato‑biliary Surgery of Chinese Research Hospital Association and Editorial Board of Chinese Journal of Digestive Surgery have organized experts in the field of hilar cholangiocarcinoma nationwide to develop the Guideline for diagnosis and treatment of hilar cholangiocarcinoma (2025 edition). The aim is to provide standardized diagnosis and treatment plans for perihilar cholangiocarcinoma based on the latest clinical practice and evi-dence-based medicine principles, to improve diagnosis and treatment levels and patient prognosis, and to provide scientific guidance and reference for surgeons in China.