Abstract: A surface light source device includes a laser beam source, a laser beam guide rod for converting a laser beam into first linear light, an LED light source, an LED light guide rod for converting LED light into second linear light, a reflecting bar having a reflecting portion for reflecting part of the first and second linear light and a diffusion reflecting portion for diffusing and reflecting a residual part of the first and second linear light, and a light reflecting portion formed in a box shape and having an opening portion with an emission side opened and a reflecting surface on an inside of the box shape. Part of the first and second linear light is reflected by the reflecting portion and the reflecting surface, and a residual part is diffused and reflected by the diffusion reflecting portion and is emitted from the opening portion.