The past decade has witnessed the booming developments of the new methodologies for noninvasive tumor treatment, which are considered to overcome the current limitation of low treating efficacy, high risk of tumor recurrence, and severe side effects. Among a variety of novel therapeutic methods, photothermal therapy, employing nanometer-sized agents as the heat generators under near-infrared (NIR) light irradiation to ablate tumors, gives new insights into noninvasive tumor treatments with minimal side effects. Although many nanomaterials possess photothermal effects, inorganic nanoparticles and polymers are the most competitive alternatives considering the high photothermal performance and good biocompatibility. In this review, we summarized the tumor photothermal therapy using the nanocomposites composed of inorganic nanoparticles and polymers. Extinction coefficient and photothermal transduction efficiency are the two main factors to evaluate the photothermal performance of nanocomposites in vitro . Considering the improvement in the stability, biocompatibility, blood circulation half-life, and tumor uptake rate after polymer coating, these nanocomposites should be designed with inorganic core and polymer shell, thus improving the tumor treating efficacy in vivo . Such structure fulfills the requirements of high photothermal performance and good bio-security, making it possible to achieve complete ablation for shallow and small tumors under the safe limitation of NIR laser power density.