A lighting device comprising: a plurality of light sources ; a light diffusion plate arranged opposite the light sources , the light diffusion plate being configured to diffuse light from the light sources ; an optical member disposed between the light diffusion plate and the light sources , the optical member including a transmitting part that is configured to transmit the light emitted from the light sources and a reflecting part that is configured to reflect the light emitted from the light sources ; and a partition arranged between adjacent light sources , wherein the optical member is a sheet-like member; the optical member is held by a support portion that is integrally provided to the partition and protrudes from an end portion of the partition toward the light diffusion plate , the support portion has a convex portion that protrudes from the end portion of the partition toward the light diffusion plate , and the optical member has an engagement portion that engages the convex portion ; wherein the convex portion has: a shaft portion that extends from the partition toward the light diffusion plate , and a widening portion that is disposed at an end of the shaft portion , has a larger diameter than the shaft portion and contacts and supports the light diffusion plate , characterised in that the widening portion is formed by swaging an end portion of the shaft portion of the convex portion during insertion of the convex portion to the optical member . a plurality of light sources ; a light diffusion plate arranged opposite the light sources , the light diffusion plate being configured to diffuse light from the light sources ; an optical member disposed between the light diffusion plate and the light sources , the optical member including a transmitting part that is configured to transmit the light emitted from the light sources and a reflecting part that is configured to reflect the light emitted from the light sources ; and a partition arranged between adjacent light sources , wherein the optical member is a sheet-like member; the optical member is held by a support portion that is integrally provided to the partition and protrudes from an end portion of the partition toward the light diffusion plate , the support portion has a convex portion that protrudes from the end portion of the partition toward the light diffusion plate , and the optical member has an engagement portion that engages the convex portion ; wherein the convex portion has: a shaft portion that extends from the partition toward the light diffusion plate , and a widening portion that is disposed at an end of the shaft portion , has a larger diameter than the shaft portion and contacts and supports the light diffusion plate , characterised in that a shaft portion that extends from the partition toward the light diffusion plate , and a widening portion that is disposed at an end of the shaft portion , has a larger diameter than the shaft portion and contacts and supports the light diffusion plate , characterised in that the widening portion is formed by swaging an end portion of the shaft portion of the convex portion during insertion of the convex portion to the optical member . <EOS>