Despite phthalocyanine has excellent photodynamic and photothermal effects as a photosensitizer and photothermal agent, hydrophobicity and aggregation limits its biological application. In this paper, phthalocyanine-cyanine co-assembled nanoparticles were designed to modulate the dimensions and morphology by introducing water-soluble cyanine. The cyanine had the ability to transform the nanomaterials from microrods to nanospheres, thus successfully constructing photoactivated nanomedicines. Their appropriate size effect and improved water solubility conferred the nanoparticles with extended blood circulation time and tumor accumulation capacity. Meanwhile, the fluorescence effect of cyanine enabled the nanoparticles to have the ability of fluorescence imaging. The nanoparticles achieved enhanced PDT/PTT synergistic effect under single laser induction, especially the generation of type I photodynamics.