A solid state radiation detector provided with sub-stripe electrodes, which is capable of reading out stored charges efficiently. A first conductive layer, a recording photoconductive layer, a charge transport layer, a reading photoconductive layer, a second conductive layer provided with stripe electrodes composed of a large number of linear elements and sub-stripe electrodes composed of a large number of linear elements, an insulating layer, and a support body are arranged in accordance with the order listed above, light-shielding films are provided on portions on the support body, which correspond to the sub-stripe electrodes and the spaces between the stripe electrodes and the sub-stripe electrodes, and thus a solid state radiation detector is constituted. In this case, when a pair of the stripe electrode and the sub-strip electrode is defined as one cycle, the cycle is set to range from 10 μm through 150 μm.