An underwater electrocution device may be used by a diver as a weapon to electrocute sharks or other underwater predators. It has a frame that defines a watertight compartment to house a motor and a generator. The motor when activated runs the generator. The electric generator is connected to a ground plate in contact with the water when the device is being used. A power supply device, such as a battery, provides power to run the motor. A spear tip is made of an electrically conducting metal. A frangible cover over the spear tip electrically insulates the spear tip, and breaks upon impact to expose the spear tip. An electrical conducting wire is attached to the trailing end of the spear tip so as to electrically connect the spear tip to the terminal of the electric generator. A spear gun ejection mechanism may be included to shoot the spear tip.
