<p>Cholangiocarcinoma (CHOL) is a tumor with high malignancy and poor prognosis, and its morbidity and mortality have increased significantly in China. The current therapeutic methods have limited efficacy and are easy to be resistant to drugs, and the targeted and immunotherapy still need precise strategy support. FANCB, the core gene of Fanconi anemia (FA) pathway, is involved in DNA damage repair and genome stability maintenance, but its mechanism of action in solid tumors, especially cholangiocarcinoma, has not been clarified. In this study, pan-cancer analysis (TCGA, ICGC, GEO databases) found that FANCB was abnormally high in a variety of cancers and was significantly associated with poor prognosis (such as shortened OS/PFS). Pathway enrichment suggests that it may affect tumor progression by regulating DNA repair, immune response and fibrosis-related pathways. In this study, based on bioinformatics analysis, the pan-cancer map of FANCB and its potential mechanism in cholangiocarcinoma were mapped.</p>