The invention relates to a method for reusing materials and/or products according to which, in a first step, a series of electrical discharges are generated between at least two electrodes in a reactor containing an ambient liquid as well as the materials and/or products to be reused, in which the series of said electric discharges produces, due to the energy, the frequency of the electric discharges as well as the voltage between the electrodes and the switching time, a mechanical shock wave which propagates across the materials and/or products to be treated in the reactor, characterized in that after a first step of embrittlement by the mechanical shock wave thus produced, the products and/or materials are exposed to a series of electric discharges in which the energy, the voltage between the electrodes that generate said discharges, the switching time and the frequency of the discharges are selected so that said discharges perform selective fragmentation of the material by the effect of an electromagnetic field. The invention also relates to a device for implementing said method.