A high-voltage electric pulse device for crushing pretreatment of ores includes an ore feeding bin, a pulse insulating barrel body, a supporting frame, a pulsation device, a product collector and a power supply. The pulse insulating barrel body and the pulsation device are assembled together, a pulsation insulating barrel body is connected with an actuating diaphragm, the actuating diaphragm is connected with an ore discharging outlet, a pulsation cone is arranged in the ore discharging outlet, the pulsation cone is hinged to a connecting rod, and the connecting rod is hinged to an eccentric wheel. Expanding and contracting devices are arranged on a cover plate, a copper bar of each expanding and contracting device is connected to a corresponding high-voltage ceramic capacitor through a high-voltage wire in parallel. A high-voltage negative pole is mounted on a screen cloth at the pulse insulating barrel body.