A breast image obtaining apparatus using a solid-sate detector, or stimulable phosphor panel capable of correctly obtaining image information up to the area closer to the chest wall of a subject. when picking up the image, the solid-state detector is moved to a place close to the side wall of the housing on the chest wall side by the moving means to pick up the image up to the area close to the chest wall, and when reading the image, it is moved to the opposite direction to secure the overrun zone between the side wall of the housing and end of the solid-state detector on the subject side. By completing acceleration or deceleration of the reading light exposure section within this zone, the scanning rate of the reading light exposure section is maintained constant across the entire region of the solid-state detector.