A radiation detector which is provided with: a flexible substrate that is formed of a resin and is provided with a plurality of pixels, which store electric charges that are generated in accordance with light that is converted from radiation, in a pixel region in a surface of a base material that has a fine particle layer containing inorganic fine particles having an average particle diameter of from 0.05 [mu]m to 2.5 [mu]m (inclusive), said surface being on the reverse side of the surface on which the fine particle layer is present； a conversion layer that converts the radiation into light and is provided on the surface of the base material, said surface being provided with the pixel region； and a reinforcing substrate which is provided on at least one of the substrate-side surface or the conversion layer-side surface of a multilayer body that is obtained by stacking the substrate and the conversion layer.放射線檢測器具備：基板，在具有微粒層的基材的與具有所述微粒層的面相反側的面的像素區域，形成有對根據從放射線變換後的光而產生的電荷進行蓄積的多個像素，所述基材為可撓性且為樹脂製，所述微粒層包含平均粒徑為0.05μm以上且2.5μm以下的無機的微粒；變換層，設置在所述基材的設置有所述像素區域的面，將所述放射線變換為光；和增強基板，設置在層疊有所述基板以及所述變換層的層疊體的所述基板側的面以及所述變換層側的面的至少一方。
