A storage electric water heater includes a tank, an inlet tube, an outlet tube, an isolating member, and a heating device, wherein the tank has a storing space. The inlet tube and the outlet tube are disposed in the tank. The isolating member is disposed in the storing space to divide the storing space into a first chamber and a second chamber. The first chamber communicates with the inlet tube and the outlet tube. The heating device is disposed in the second chamber and includes a tube body and a heating element. Two ends of the tube body communicate with the first chamber, so that water in the first chamber could enter an interior of the tube body. The heating element is disposed on a tube wall of the tube body. Thermal energy generated by the heating element could be transferred to the interior of the tube body via the tube wall to heat up water in the tube body, thereby facilitating the thermal convection of water in the first chamber.