Red blood cells are attached to iron oxide nanoparticles pre-coated with chlorine e6, a photosensitizer, and then loaded with a chemotherapeutic drug, doxorubicin, to enable imaging-guided combined photodynamic and chemotherapy of cancer, achieving excellent synergistic therapeutic effects in an animal tumor model. This work highlights the great promise of integrating cell-based drug-delivery systems with nanotechnology as a biocompatible multifunctional platform for applications in cancer theranostics.