Abstract: The present invention relates to alpha-form zinc-phthalocyanine nanowires (ZnPc NWs) having enhanced water solubility and water dispersibility, to a composite of an alpha-form zinc-phthalocyanine nanowire/phenothiazine, to a method for preparing same, and to a photosensitizer including same or a pharmaceutical composition including same for preventing or treating cancers. Since the alpha-form zinc-phthalocyanine nanowires or the composite of alpha-form zinc-phthalocyanine nanowire/phenothiazine according to the present invention exhibit dual traits, i.e., photothermal and photodynamic traits in single molecules, they are very useful for the development of a multifunctional molecular system and can also be usefully applied to light therapy of cancers due to their good light therapeutic effects.