Abstract: Aiming at the problem that inappropriate power price strategy can change peak-valley characteristics of load curve, which causes electricity consumption period to be re-divided frequently, firstly,the price elasticity matrix of demand（PEMD） is improved by introducing the elasticity effect weights, and the user response model is established. Secondly, the peak and valley periods of load are divided based on fuzzy clustering. Finally, aiming at the minimum load peak and load fluctuation coefficient, a decision model of peak-valley TOU price was established, and the influence of peak-valley inversion on optimization results was discussed. The results show that this method can keep the original hill valley characteristics of load curve, and reduce the load fluctuation.