A photodetection type coordinate input device includes a frame having a substantially rectangular opening formed in the center, a light-emitting element array composed of a plurality of light-emitting elements disposed along each of the two sides of the opening of the frame, a light-receiving element array composed of a plurality of light-receiving elements disposed along each of the two sides which respectively oppose the first two sides, and a filter provided in a part or the whole area of the opening and adapted to transmit desired light alone. The opening of the frame is disposed in front of a display to form a plurality of optical paths by pairs of light-emitting and -receiving elements, respectively, in front of the display screen of the display, and a position at which optical paths are blocked is detected to specify a coordinate position on the display screen, thereby inputting the coordinate position. The coordinate input device is provided with a recess for blocking the propagation of light toward the light-receiving element side. The recess is disposed in a region within the filter section which is closer to at least the light-receiving element side than a position which is located on the downstream side in a direction in which the light emitted from the light-emitting elements travels and which position is at a mid point between the light-emitting and -receiving elements.