A wavelength conversion device (1) includes a light source (11) for emitting light having a predetermined wavelength in a wavelength region from ultraviolet light to visible light, a phosphor layer (13) for performing wavelength conversion on light which is emitted from the light source (11) and incident on an incidence face, and an optical member (12) which is arranged between the light source (11) and the phosphor layer (13), splits and separates light emitted from the light source (11) and emits the split and separated light beams to the incidence face of phosphor layer (13).