Combination of photodynamic therapy (PDT) and photothermal therapy (PTT) generally requires different components to build a composite irradiated with different excitation lights. One component photoactive agent for enhanced combination of PDT and PTT under the excitation of a single wavelength light source is more urgent in tumor phototherapy via adjusting spatial arrangement of photoactive units. Herein, porphyrin-based covalent organic framework nanoparticles (COF-366 NPs) were synthesized to control the orderly spatial arrangement of the photoactive building units and firstly used for antitumor therapy in vivo. COF-366 NPs provide the simultaneous therapy of PDT and PTT under a single wavelength light source with the monitoring of photoacoustic (PA) imaging, which makes the operation simpler and more convenient. COF-366 NPs had achieved good phototherapy effect even in the face of large tumors. The prepared multifunctional COF-366 NPs open up a new avenue to phototherapeutic materials and expand the application range of covalent organic framework.