[Problem] The purpose of the present invention is to provide a secondary battery charging/discharging apparatus, wherein a structure for mounting a contact unit and a magazine is improved, said contact unit and magazine to be housed in a case, and safety and workability of the contact unit at the time of attaching/detaching the contact unit are also improved. [Solution] This invention is characterized in that: a sliding mechanism is attached to a bottom portion in a case mounted on a rack; a contact stage having a contact unit attached thereto can be transferred by means of the sliding mechanism to the inside and outside of a case, said contact unit being provided with a secondary battery chuck mechanism; and a magazine can be transferred to the inside and outside of the case by means of the sliding mechanism, said magazine housing a plurality of secondary batteries in parallel by having electrode terminals facing the chuck mechanism.