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 region for reflecting part of the first linear light and the second linear light and a transmitting region for transmitting a residual part of the first linear light and the 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. In the first linear light and the second linear light, part thereof is reflected by the reflecting region and the reflecting surface and a residual part is transmitted through the transmitting region and is emitted from the opening portion.