Provided are color imaging elements, photosensors and photoelectric transducers that use proteins and are capable of long term, stable usage, as well as manufacturing methods therefor. Zinc-substituted cytochrome c552 (13) is fixed on a gold electrode (11) via a self-organizing monomolecular film (12) to form a photoelectric transducer for blue light. Alternatively, cytochrome c552 is fixed on a gold electrode via a self-organizing monomolecular film and a fluorescent protein that absorbs blue light is bound to said cytochrome c552 to form a blue light photoelectric transducer. Said photoelectric transducers are used as blue light photoelectric transducers in color imaging elements or photosensors.