A light source device includes a first light source 33, a second light source 35 having an emission wavelength that is different from the first light source 33, and a phosphor 43 that is disposed to be distant from the first light source 33 and the second light source 35 and absorbs light in a predetermined excitation wavelength band to emit fluorescence. The phosphor 43 is disposed on an emission light optical path that is shared by the first light source 33 and the second light source 35. The emission wavelength of the first light source 33 is in the predetermined excitation wavelength band. The emission wavelength of the second light source 35 is outside of the predetermined excitation wavelength band.