An electric pulse decomposition method for separating a composite material by an electric pulse, the composite material being obtained by bonding or joining a plurality of conductors to each other with an insulating member, the electric pulse decomposition method including a protrusion formation step for forming a protrusion in a specific site, on a side on which the composite material is arranged, of at least one of the plurality of conductors, and a separation step for separating the plurality of conductors in the composite material 1 by respectively bringing electrodes into contact with surfaces of the plurality of conductors and applying an electric pulse between the electrodes to destroy the insulating member. This makes it possible to separate the plurality of conductors from the composite material by making a shock wave caused by a current of the dielectric breakdown functioning as an adhesive to effectively destroy the insulating member.