Cys-AuNRs were prepared via ligands exchange method using zwitterionic cysteine to modify AuNRs for the clinical photothermal therapy. And the photothermal effect, the infrared thermal imaging, hyperthermia effect on tumor cells and fluorescence imaging experiment of Cys-AuNRs were investigated under irradiation by an 808 nm NIR laser at a power density of 200mW∙cm-2. The survival rate of HeLa cells incubated with Cys-AuNRs at the concentration of 57 μg/mL, still remains 90.1%. However, under NIR irradiation for10 min , the survival rate of Hela cells sharply decreases to 60.1%. The results suggest that Cys-AuNRs have good biocompatibility and low cytotoxicity, can also kill tumor cells effectively under the laser radiation. Therefore, the modification of AuNRs with biocompatible cysteine has an important practical significance in the clinical noninvasive hyperthermia treatment.