A planar light source emits planar light by power supplied from a mounting member. The planar light source includes an engaging part, a planar-light-emitting panel having a light-emitting surface, and a connecting unit disposed between the engaging part and the planar-light-emitting panel. The engaging part forms a portion of a power supply path for supplying power from the mounting member to the planar-light-emitting panel. The planar-light-emitting panel includes a planar-light-emitting tile and a translucent plate, where one main surface of the planar-light-emitting tile includes a light-emitting region. The planar-light-emitting panel emits, in a lighting state, the planar light from the light-emitting region of the planar-light-emitting tile through the translucent plate. An output of the planar light from the planar light source is adjusted by pressing the light-emitting surface.