Provided is a radiation sensor comprising: a phosphor layer that converts incident radiation into converted light containing a first light component having a first wavelength region that includes a maximum peak wavelength different from a maximum peak wavelength of the radiation, and a second light component having a second wavelength region of 400 nm to 460 nm, different from that of the radiation and the first wavelength region; an organic photoelectric conversion layer; and an insulating substrate provided with a charge detection layer, and that includes a storage capacitor and a thin film transistor having an oxide semiconductor active layer, wherein the first and second light components each pass through the organic photoelectric conversion layer and arrive at the oxide semiconductor active layer, and wherein an intensity of the second light component is lower than an intensity of the first light component.