An illumination device with a toning function in which possibility of moisture and dust intruding into the case is reduced with a simple mechanism is realized. The illumination device includes a light emitting element light source (17) mounted on a substrate inside the case unit (21), an external gear-shaped fluorescent-substance plate (41) having a configuration in which a light emitting color of an applied fluorescent substance differs according to position and being arranged above the light emitting element light source (17) inside the case unit (21), and an internal gear-shaped adjustment ring (43) arranged so as to mesh with the external teeth of the fluorescent-substance plate (41), wherein the adjustment ring (43) is arranged to be positioned on the outer periphery of the main body under a lens dome (11), and when the adjustment ring (43) is rotated, a relative positional relationship between a color distribution applied on the fluorescent-substance plate (41) and the light emitting element light source (17) is changed.