Hepatocellular carcinoma(HCC)and biliary tract cancer(BTC)are significant health challenges in China because of their high prevalence and mortality rates.Advances in molecular diagnostics have opened new avenues for personalized treatment strategies.This consensus provides a comprehensive update on the clinical applications of molecular diagnostics in HCC and BTC and addresses the urgent need for personalized treatment strategies tailored to the Chinese population,emphasizing the importance of molecular markers in guiding targeted therapies and immunotherapies.By employing the Delphi method and the Grading of Recommendations Assessment,Development,and Evaluation system,the expert panel formulated evidence-based recommendations for the use of molecular diagnostics in the clinical management of HCC and BTC.Key molecular markers,such as isocitrate dehydrogenase(IDH)1 and 2,fibroblast growth factor receptor 2(FGFR2),BRAF V600E,human epidermal growth factor receptor 2(HER2),rearranged during transfection(RET),and neurotrophic tyrosine receptor kinase(NTRK),are highlighted for their roles in optimizing treatment regimens.The consensus also explores the signifi-cance of emerging biomarkers,such as tumor mutation burden and microsatellite instability,in pre-dicting responses to immune checkpoint inhibitors.The recommendations aim to enhance precision medicine approaches,improve patient outcomes,and foster the integration of molecular diagnostics into routine clinical practice.