T cell receptor （TCR） is a key molecule mediating anti-tumor immunity， and its diversity profile （TCR repertoire） serves as a biomarker of host immune status. The development of high-throughput sequencing technologies has revolutionized the application of TCR repertoire analysis in cancer immunotherapy. The clinical value of TCR sequencing in individualized tumor treatment is increasingly prominent. Through monitoring immunotherapy response and predicting survival outcomes， TCR sequencing provides critical guidance for precision tumor therapy.