A polygonal capacitor including a polygonal capacitor case having an engaging portion at an inner surface thereof; a capacitor element accommodated in the polygonal capacitor case; a plurality of terminals respectively connected to a plurality of electrodes of the capacitor element through a base portion of each terminal; an insulating terminal base to which the terminals are fixed; and a resin filled in the polygonal capacitor case. An engaging member formed at the insulating terminal base is in pressure contact with the engaging portion of the polygonal capacitor case.
