A light source device comprising: a first light source adapted for emitting light in a first wavelength band; light-source light generation means (24, 25) adapted for generating light of each of a plurality of colors by time division by using the first light source; a second light source adapted for generating light of a second wavelength band different from the first wavelength band; and a light source control means adapted for causing each of the light-source light generation means (24, 25) and the second light source to generate light and for controlling a drive timing of each of the first and second light sources (20, 21) to adjust a light-emission timing, characterized in that the first light source is adapted for emitting a laser light of a blue wavelength band, and the light-source light generation means (24, 25) is a color wheel providing at least a fluorescent substance layer for generating light of a green wavelength band using the laser light as excitation light and a diffusion layer for transmitting the laser light, said layers jointly formed into a ring-like shape along a circumferential direction of the color wheel; the second light source is a light-emitting diode or a laser light source adapted for emitting red wavelength band light; the light source control means is further adapted for operating in either one of at least two different color modes by adjusting a ratio of light-emission periods of red, green, and blue by controlling the drive timing of each of the first and second light sources (20, 21); wherein at least one light emission period of the second light source is a light emission period extending into both adjacent periods wherein the fluorescent substance layer and the diffusion layer are situated in an irradiation position of the laser light in the color wheel, and wherein, during said at least one light-emission period of the second light source, an oscillation of the laser light of the blue wavelength band is stopped. a first light source adapted for emitting light in a first wavelength band; light-source light generation means (24, 25) adapted for generating light of each of a plurality of colors by time division by using the first light source; a second light source adapted for generating light of a second wavelength band different from the first wavelength band; and a light source control means adapted for causing each of the light-source light generation means (24, 25) and the second light source to generate light and for controlling a drive timing of each of the first and second light sources (20, 21) to adjust a light-emission timing, characterized in that the first light source is adapted for emitting a laser light of a blue wavelength band, and the light-source light generation means (24, 25) is a color wheel providing at least a fluorescent substance layer for generating light of a green wavelength band using the laser light as excitation light and a diffusion layer for transmitting the laser light, said layers jointly formed into a ring-like shape along a circumferential direction of the color wheel; the second light source is a light-emitting diode or a laser light source adapted for emitting red wavelength band light; the light source control means is further adapted for operating in either one of at least two different color modes by adjusting a ratio of light-emission periods of red, green, and blue by controlling the drive timing of each of the first and second light sources (20, 21); wherein at least one light emission period of the second light source is a light emission period extending into both adjacent periods wherein the fluorescent substance layer and the diffusion layer are situated in an irradiation position of the laser light in the color wheel, and wherein, during said at least one light-emission period of the second light source, an oscillation of the laser light of the blue wavelength band is stopped.