Abstract: Photothermal tumor therapy with second near-infrared (NIR-II, 1000-1350 nm) phototriggered photothermal agents is a promising emerging method of tumor therapy. Transition metal carbides, nitrides, and carbonitridges compounds (MXenes) have advantages such as ultra-thin layered structure, unique electronic properties, large specific surface area, high photothermal conversion efficiency, good hydrophilicity, and easy surface functionalization, making them suitable as photothermal agents for tumor photothermal therapy. This review introduces the advantages of NIR-II photothermal therapy, summarizes the photothermal performance of MXenes and the stability of MXenes colloidal solution. At the same time, the research progress of MXenes in NIR-II tumor photothermal therapy was discussed, and the challenges and opportunities faced in the future development of this field were elaborated.