Provided are an illumination device and a display apparatus capable of reducing generation of an interference pattern, while achieving downsizing and enhancing light use efficiency. An illumination device includes: a light source section that includes a laser light source; an optical device disposed on a light path through which laser light from the laser light source travels; an optical member that outputs illumination light; and a driving section that displaces a relative position between the optical device and the optical member to vary at least one of an incidence position and an incidence angle, in an incidence surface of the optical member, of the laser light.