A light source apparatus including a light source configured to emit a light flux from an emission region having a predetermined size and a rotationally symmetrical emission intensity distribution; and a condenser configured to condense the light flux to allow the light flux to exit to the outside. The condenser is rotationally symmetrical about an optical axis and is disposed to surround the emission region, and has four or more reflection mirrors each having a reflecting surface for reflecting the light flux emitted from the emission region. The reflection mirrors include elliptical surface reflection mirrors where the reflecting surface is elliptical and spherical surface reflection mirrors where the reflecting surface is spherical, and are alternately arranged in the direction of the optical axis, and a light flux reflected by one spherical surface reflection mirror is further reflected by one elliptical surface reflection mirror oppositely disposed across the emission region.