Disclosed is an apparatus for sterilizing a food or a medical appliance. The apparatus includes a sterilization tank, electrode rods arranged to face each other at both sides of the bottom surface of the sterilization tank and made of a conductive metal selected from Pt, Au, Ag, Cu, Sn, and alloys thereof, the electrode rod at one side being connected to a positive (+) electrode and the electrode rod at the other side being connected to a negative (−) electrode, and a field effect transistor connected to the electrode rods through 2.0 to 5.0 mm thick electric wires. When electric power is applied to the electrode rods, a content in the sterilization tank is instantaneously sterilized by electrical energy. The apparatus can kill microbial bacteria by a physical process for instantaneous sterilization including applying electrical energy to an object in need of sterilization in a food or a medical appliance. Also disclosed is a method of using the apparatus.
