A projector includes: a light source unit; an optical apparatus including, an optical device, a holding frame for holding a periphery of the optical device, a cooling tube that is provided in the holding frame along the periphery of the optical device and in which a cooling fluid flows, whereina gap between the holding frame and the cooling tube is filled with a thermally conductive material; a cooling unit for circulating the cooling fluid in the optical apparatus; and a projection optical apparatus for enlarging and projecting an optical image formed by means of the optical apparatus.