With the development of electric power market, the differentiated electricity price mechanism provides a new way to guide electric vehicles (EVs) to charge orderly. Therefore, an optimal regional peak-valley time-of-use price (RPTP) calculation model for electric vehicles orderly charging is proposed in this paper. First, the electricity consumption area is divided into four regions: residential area, office area, industrial area and commercial area by the differences in electricity consumption of urban areas, and the peak-valley time-period division of RPTP is studied by the method of membership function. Subsequently, the performance of user response to the RPTP is analyzed by the elastic coefficient method. Finally, with minimizing the peak valley difference and user charging cost, a calculation model of optimal RPTP for EVs is established. The simulation results verify the effectiveness of the proposed model on reducing user charging cost and peak valley difference. Also, EVs can be coordinated to charge orderly.