Abstract: Task The invention provides an optical source device and a projector including the optical source device, in which a microwave is used to reduce the size, and increase the life span. Means for Resolution The optical source device according to the invention includes a solid high frequency oscillating unit that outputs a high frequency signal, a waveguide that receives the high frequency signal output from the solid high frequency oscillating unit and radiates the received high frequency signal as a microwave, and a light emitting unit that emits light by the microwave radiated from the waveguide unit. A container of the waveguide unit has a space surrounded by reflective surfaces that reflect the microwave radiated from the antenna unit so as to collect the microwave.