Provided is an infusion pump in which one or more occlusion sensors includes a Hall element detecting a variation in magnetic flux, of one or more magnets, generated with movement of a plunger caused by a variation of an infusion tube in a radial direction that results from an occlusion of the infusion tube, and changing the variation of an infusion tube in the radial direction into an output voltage. When increasing a movement distance of the plunger to a plurality of predetermined positions D1 to D4, a control unit obtains linearity of output voltages PV1 to PV4 of the Hall element with respect to movement distances to a plurality of positions D1 to D4 by applying a plurality of predetermined impression voltages BE1 to BE16 to the Hall element to select from the plurality of impression voltages applied for each of the movement distances to the plurality of positions.
