The invention relates to a light source device. The light source device comprises a laser light source, a refraction optical element, a light conversion device and a light collection device; the laserlight source is used for emitting first light; the refraction optical element is arranged on the emergent light path of the laser light source and is used for guiding the first light into the light conversion device; the refraction optical element comprises an emitting plane; light refracted by the emitting plane of the refraction optical element is emitted towards the direction of the light conversion device in a deviated mode; the light conversion device is arranged on the emergent side of the refraction optical element; the entering plane and emitting plane of the light conversion device are the same plane; the Brewster angle of the medium of the entering plane of the light conversion device is alpha; the emergent light of the refraction optical element obliquely enters the light conversion device at an incident angle of alpha-20 degrees to alpha+10 degrees; and the light collection device is arranged on the emergent side of the light conversion device and is used for collecting light emitted by the light conversion device and then emitting the light. According to the light source device, a compact light path structure is realized, and meanwhile, an emergent light spot with a uniform and consistent color can be obtained.