A projection apparatus has a light source module including a light-emitting element, an optical path switching element, a wavelength conversion element, a first reflection element, and a first beam splitter element. The optical path switching element switches a first color beam between a first optical path and a second optical path. When the first color beam is switched to the first optical path, the first color beam is propagated to the wavelength conversion element to excite a first and second wavelength conversion layers on the wavelength conversion element to produce a second color beam and a third color beam. When the first color beam is switched to the second optical path, the first color beam is propagated to the first reflection element.