The present study was the first to use multi-level data from different databases to perform a CXCL13 expression-based pan-cancer analysis and the results indicate that CXCL13 can be used as a risk or prognostic factor for many cancers, and it plays an important role in tumor immunity by affecting TMB, MSI and tumor infiltrating immune cells. This evidence concerns the gene CXCL13 and neoplasm.