A vehicle lighting system having: a light guiding member having a front face as a light emitting surface, a rear face having a plurality of reflecting portions inclined to the front face, and a side face; and a light source disposed opposite to the side face. An angle θ defined between the front face and the side face is designed such that, of external lights to enter into the light guiding member, a light to travel directly to the side face can be totally reflected on an interface of the side face.