The invention discloses a photoelectric element, a back light module device and an illuminating device. The photoelectric element comprises a first light-emitting structure and a second light-emitting structure, wherein the first light-emitting structure can emit first wavelength light, and the second light-emitting structure can emit second wavelength light; the first light-emitting structure isa nano-column structure and is provided with a first active layer; and the first active layer can absorb the second wavelength light and generate the first wavelength light.