Provided are a photosensitizer-metal nanoparticle charge complex and a composition for photodynamic therapy or diagnosis containing the same. The complex includes a metal nanoparticle, a photosensitizer charged with a first charge, and a linker bound to the metal nanoparticle and charged with a second charge having an opposite polarity to the first charge. During circulation in blood, the photosensitizer-metal nanoparticle charge complex is maintained in a complex type, and thus duration of a side effect of photosensitivity can be reduced. In a tumor tissue, the complex is specifically accumulated, but in a normal tissue, it is difficult for the complex to penetrate. Thus, the complex can selectively destroy the tumor tissue. Moreover, selective fluorescence in the tumor tissue can provide further improvement in accuracy of diagnosing a tumor using the complex.