A rotary input device includes a first annular magnetic body in which a plurality of outward protrusions protruding toward an outside in a radial direction are disposed along a circumferential direction, a second annular magnetic body in which a plurality of inward protrusions formed to oppose the outward protrusions of the first magnetic body are disposed along a circumferential direction, and a rotary knob configured to relatively rotate the first magnetic body and the second magnetic body. The first magnetic body includes a magnet in which opposing surfaces facing each other are vertically disposed and which is magnetized to two poles of an upper pole and a lower pole including the opposing surfaces, a pair of yokes that interposes the opposing surfaces of the magnet vertically, and the outward protrusion formed on the pair of yokes.