A radiation detecting apparatus includes a radiation detector including a scintillator for converting radiation that has passed through a subject into visible light, and a substantially cuboid shaped photoelectric transducer board for converting the visible light into radiographic image information, and a casing housing the radiation detector therein. The casing is of a substantially cuboid shape and includes an upper plate, a lower plate, and a frame interconnecting the upper plate and the lower plate. The frame has a recess defined therein, which faces and is spaced from a corner of the photoelectric transducer board, the recess being concave in a direction away from the corner.