A planar light-emitting device having a plurality of light units each including a light source and a lightguide member that guides light received from the light source through an end surface serving as a light-entrance surface disposed to face the light source and that emits the light from an upper surface and two mutually opposing side surfaces after changing the optical path of the light, and further has a reflecting member having a light-reflecting surface on which the light units are disposed. The lightguide member has an elongated shape. The light units are disposed in linear arrays each in which the light units are linearly disposed in series in the elongated direction of the lightguide member. The linear arrays extend in the elongated direction of the respective lightguide members. The linear arrays extend in parallel with each other and are spaced from each other in a width direction perpendicularly intersecting the elongated direction of the lightguide members.