To provide a light source device capable of controlling temperature without adding an extra component, and to provide a projector having the same.

The light source device includes: a light source lamp 18 that radiates light; and a reflector 21 that accommodates a light source lamp 18, has an open face from which light from the light source lamp 18 is emitted, and reflects light from the light source lamp 18 by its internal face, thereby emitting the light from the open face. An upper reflecting film 21b and a lower reflecting film 21c, which reflects heat less than the upper reflecting film 21b, are formed on the internal face of the reflector 21.