A light source device, including: an excitation light source; a supplementary light source; and a color wheel, the excitation light source emits first color light to the color wheel, the color wheel includes a first light-emitting region and a wavelength conversion region sequentially arranged along circumferential direction, and a supplementary light-emitting region located on inner or outer side of the wavelength conversion region, the first light-emitting region receives the first color light in a first time period and emit it, the wavelength conversion region receives the first color light in a second time period and emit excited light, and the supplementary light source emits, during the second time period, a supplementary light that broadens a color gamut and at least partially overlaps with a spectrum of the excited light, and the supplementary light from the supplementary light-emitting region is combined with the excited light from the wavelength conversion region.