An optical module includes a wavelength variable interference filter having a fixed reflective film, a movable reflective film which faces the fixed reflective film with a gap between reflective films interposed therebetween, and an electrostatic actuator that changes the gap between reflective films, and a gap control unit that controls the electrostatic actuator. The gap control unit controls the electrostatic actuator on the basis of an order which is set in accordance with a wavelength to be measured, and changes the gap between the reflective films.