A backlight unit 12 according to the present invention includes LEDs 17 as light sources, an LED board 18 mounting the LEDs 17 thereon, a chassis 14 that stores the LED board 18 therein and includes an attachment hole 14e, a body portion 24 that sandwiches the LED board 18 between the body portion 24 and the chassis 14 and holds the LED board 18, and a board holding member 20 including an attachment portion 25 that is protruded from the body portion 24 toward the chassis 14 to be inserted into the attachment hole 14e, and the board holding member 20 is configured to be rotatable along a plate surface of the chassis 14 between a holding position at which the attachment portion 25 overlaps with an edge of the attachment hole 14e in a plan view and sandwiches the edge of the attachment hole 14e between the attachment portion 25 and the body portion 24 and a non-holding position at which the attachment portion 25 does not overlap with the edge of the attachment hole 14e in a plan view and attaching and detaching of the attachment portion 25 from the attachment hole 14e is allowed.