The variable spectroscopic element includes a pair of optical substrates 21-22, four sensors 31-34, four piezoelectric elements 41-44, and a control section. The sensors 31, 33 are arranged to form symmetry with respect to the center axis, which links gravity centers of mutually facing surfaces of the optical substrates 21-22, and so are the sensors 32, 34. The control section calculates, from signals of the sensors 31-34, a distance x between the gravity centers of the mutually facing surfaces, and angles θ, φ each of which is formed by a plane perpendicular to the center axis and the facing surface of the movable substrate 22, to drive the piezoelectric elements 41-44 on the basis of the distance x, the angles θ, φ, and to carry out feedback control and feed forward control with respect to at least one of the distance x, the angle θ, and the angle φ.