The purpose of the present invention is to realize a display device of high definition and high contrast by applying an accurate local dimming. The structure of the invention is as follows. A display device including: a display panel and a back light; in which the back light includes a light source and optical sheet group; the light source includes the light source substrate and LEDs disposed on the light source substrate; the light source is divided into segments in a plan view; at least one of the LEDs is disposed in a segment; the light source substrate, except the LEDs, is covered by a protective film; the segment is partitioned as by wall with the partition plate made of resin; the partition plate is disposed on the protective film.