Abstract: A light source apparatus including a light source, an optical fiber, a light guide module, and a light shape adjustment element is provided. The light source emits a light beam. The optical fiber disposed in a transmission path of the light beam has a light incident end and a light emitting end. The light beam enters the optical fiber through the light incident end and leaves the optical fiber through the light emitting end. The light guide module has a first surface, a second surface opposite to the first surface, and a light incident surface connecting the first surface and the second surface. The light beam from the light emitting end enters the light guide module through the light incident surface. The light shape adjustment element is connected to the light guide module and capable of changing a light shape of an emitted light from the light guide module.