A reactor includes a core body having at least three iron cores composed of a plurality of stacked magnetic plates and an end plate and a pedestal which are connected to the core body so as to interpose the core body therebetween. Gaps are formed between the at least three iron cores, through which magnetic connection can be established. An unevenness absorbing member is arranged at least one of a region between an end plate and the core body and a region between the core body and a pedestal, for absorbing unevenness in heights of the at least three iron cores in the axial direction of the core body.