The U-shaped flexural electrothermal actuators were simulated based on the BP artificial neural network and stochastic finite element method. First the maximal displacement of the actuators,whose concrete sizes affect the geometrical structure,was solved by the finite element method. The relation between the response and the input was simulated through the BP neural network. The Monte Carlo method was applied to get efficient sample data and to analyze the errors. The results show that the proposed method is feasible and effective.