Background and objectivesStudies have shown that serum ferritin (SF) has unfavourable prognostic value in hepatobiliary and pancreas (HBP) cancers. This meta-analysis aimed to comprehensively assess the prognostic role of pretreatment SF in patients with HBP cancers.MethodsEligible studies published before January 2020 were obtained through a comprehensive search in the PubMed, Web of Science, Cochrane Library and EMBASE databases. Pooled HRs and 95% CIs were then employed as effect sizes.ResultsSeven studies comprising 1244 patients were pooled. Elevated pretreatment SF was associated with worse overall survival (OS) (HR 1.60, 95% CI 1.36 to 1.88, p<0.001) and recurrence-free survival/progression-free survival/time to recurrence (HR 1.70, 95% CI 1.15 to 2.52, p=0.008). Significant prognostic value of elevated pretreatment SF on OS was detected in the subgroups regardless of the cancer type, race, SF cut-off value, tumour-node-metastasis stage and Newcastle-Ottawa Scale score.ConclusionElevated pretreatment SF was associated with worse survival outcome of patients with HBP cancers. As such, it may serve as a novel prognostic biomarker for HBP cancers.