The purpose of the present invention is to provide a projection type image display apparatus which is simple in configuration, low in price, and improved in reliability and brightness of an illumination light source. The present invention is a projection type image display apparatus provided with: a lamp; a reflector that reflects a light flux emitted from the lamp; a collimating lens that collimates the light reflected by the reflector; a light modulation device that modulates the collimated light to output the modulated light; and a projection lens that projects the modulated light. The reflector is configured to prevent the lamp from being irradiated with the reflected light of the light flux emitted from the lamp, and the collimating lens is formed of one biconcave lens having concave surfaces on both the incident side and the exit side.