A pulse current assisted extrusion forming device and an extrusion forming method relate to an extrusion forming device and a method thereof. The invention solves the problems that the existing extrusion forming device is great in heat loss, and long in heating time, and the existing extrusion forming method is complicated in technical process flow, low in work efficiency and non-homogenous in distribution of density of the current produced inside the blank on the cross-section and easy to cause skin effect. A current-conducting female mold of the device is arranged in a mold cavity of an insulating outer film; a current-conducting male mold and the current-conducting female mold are used as electrodes and connected on a high frequency pulse power source; the pressure within the range of 5-200MPa is applied to the current-conducting male mold by an upper pressure head according to a yield strength value at the temperature selected by the blank to be formed so that the blank is extrudedto be a required shape by the mold after plastic extrusion deformation; the device has high heating speed and improves the work efficiency; and the method uses the heat effect of pulse current and the electro-plastic effect, thereby obviously improving the forming efficiency of the blank, increasing the material plasticity and saving the energy resource.