The light source device for an endoscope includes a plurality of light sources that emits light with different wavelengths, a light path integration part that integrates light paths of the light, a light path unit on which the integrated light is incident, a photodetector that receives a portion of the light until the light paths are integrated by the light path integration part to obtain information on a light quantity, and a light source controller that adjusts the light quantity of the light based on a light quantity measurement signal generated by the photodetector. The light path unit includes a light guide part that has a homogenizing function to receive the integrated light from the light path integration part, and a light collecting part that collects light passing through the light guide part.
