The invention discloses a load control method based on an electric water heater load group model. The method comprises the following steps that 1), an electric water heater model with water flowing ina water tank considered is established; 2), clustering is carried out on electric water heater indexes in a load dispatching center control area on the basis of probability distribution, and an electric water heater load group probability model is established; 3), a heat storage state variable of the electric water heater and a calculation method of the heat storage state variable are defined according to the water temperature in the electric water heater; and 4), controllable subsets of the water heater load group are selected according to the extent of the heat storage state of the water heater in the load group, the controllable subsets of the load group of the water heater are sequenced on the basis of a sequencing method taking the comfort level of a user into consideration, and theload control is completed according to the sequencing result. According to the method, due to the fact that the temperature distribution and the natural convection process in the electric water heaterare considered, the model is objective and accurate; and the heat storage state is defined, so that the comfort level of the user is guaranteed to a certain extent, and a great assistant effect is applied for propelling the temperature control to reach and participate in the power grid frequency control.