A disclosed light source device comprises: a reflective sheet having a through hole formed therein; a light source located in the through hole and including a light emitting diode; and a substrate to which the light emitting diode is attached, the substrate including a protective layer provided on one side facing the reflective sheet, wherein the protective layer includes a first protective layer disposed adjacent to the light emitting diode, and a second protective layer having a reflectance lower than that of the first protective layer.