Provided are a light source device and a display device with an assembly constitution that can reduce the size of a frame and make the frame less conspicuous. A light source device is constituted such that a front cabinet having a U-shaped cross-section and a front cover are attached as a unit on an outer peripheral part of a backlight unit, and A display device is constituted such that the front cabinet having a U-shaped cross-section and the front cover are attached as a unit on an outer peripheral part of a liquid-crystal unit, a lens cover is attached by joining joining-groove parts to lens fixing claws provided on the front cabinet and the peripheral edge part of the lens cover is held by a pressing piece on the front cover.