To obtain an LED linear light source which exhibits high heat dissipation and also can reduce the amount of warp, and a backlight using the LED linear light source.

An LED linear light source (1, 100, 200) of the prevent invention comprises: a slender metal base substrate (10); a plurality of LED chips (6) mounted in a row on the metal base substrate (10); and a light-transmissive encapsulation resin (8) covering the LED chips (6). The encapsulation resin (8) constitutes island-shaped sealing parts (20) which are disposed in shape of islands and at an equal pitch on a laminate structure layer along the longer direction of the metal base substrate (10), each of the island-shaped sealing parts (20) covering an LED chip group (16, 216) composed of a conductive foil layer (13) and a plurality of electrically connected LED chips (6) and being secured to a heat radiation member with a screw (2) of a between-island part (30). This construction helps to prevent a warp in the LED linear light source.