Viologen-linked porphyrins are a typical compound for photoinduced electron-transfer models via the photoexcited singlet state. The singlet-state electron transfer, however, does not occur in water, because solvent cage formation, which is motion of solvent molecules during electron transfer, is slow in the case of water. In order to boost the solvent cage formation of water and achieve the electron transfer via the singlet state in water, viologen-linked hydrophobic porphyrin was prepared.