To provide a stereoscopic image photographing device capable of preventing the deterioration of image quality and obtaining a high resolution stereoscopic image.

A pair of mirrors 31R1, 31L1 and a pair of mirrors 31R2, 31L2 almost parallel to the mirrors 31R1, 31L1 are provided with a prescribed angle (for example, 45°) to a lens 3 ahead of the lens 3 of a camera 1, and an optical axis 30L and an optical axis 30R are given by leaving a distance (d) (interpupillary distance) which is a factor to determine a parallax. Then, a mirror 31L3 and a mirror 31R1 are provided on the image-forming side of the lens 3 corresponding to the optical axis 30L and the optical axis 30R with a prescribed angle. A right and left optical paths are separated, and a CCD32L and a CCD32R are respectively provided on each image forming position. Thereby, each right and left image can be photographed by using all of the pixels of the CCD32L and 32R. Thus, a stereoscopic image based on the device does not incur degradation of image quality.