Projector

A projector includes a resin-made lamp case in which a light source lamp is fitted and a metal-made optical part holder in which an optical part is fitted. Preferably, the lamp case includes a positioning boss, the optical part holder includes a resin-made lamp case holder which accommodates the lamp case, a tubular light tunnel which shapes a form of light, a cylindrically shaped portion having a guide hole into which the positioning boss is inserted, and a resiliently deformable detent member, a metal-made light-tunnel fixing member, the detent member is substantially U-shaped and is provided integrally on the light-tunnel fixing member, the cylindrically shaped portion has a slot portion into which the detent member is inserted and which extends from an outer peripheral surface to the guide hole, and the positioning boss has a concave engaging portion which is engaged with the detent member.