We propose the use of folate-receptor-targeted, near-infrared-sensitive polydopamine nanoparticles (NPs) for chemo-photothermal cancer therapy as an enhanced type of drugdelivery system which can be synthesized by in situ polymerization and conjugation with folic acid. The NPs consist of a Fe3O4/Au core, coated polydopamine, conjugated folic acid, and loaded anti-cancer drug (doxorubicin). The proposed multifunctional NPs show many advantages for therapeutic applications such as good biocompatibility and easy bioconjugation. The polydopamine coating of the NPs show a higher photothermal effect and thus more effective cancer killing compared to Fe3O4/Au nanoparticles at the same intensity as near-infrared laser irradiation. In addition, the conjugation of folic acid was shown to enhance cancer cellular uptake efficiency via the folate receptor and thus improve chemotherapeutic efficiency. Through in vitro cancer cell treatment testing, the proposed multifunctional NPs showed advanced photothermal and chemotherapeutic performance. Based on these enhanced anti-cancer properties, we expect that the proposed multifunctional NPs can be used as a drug-delivery system in cancer therapy.