The value － added service of premium power supply is an important way for power companies to improve the competitiveness of power selling． Premium power supply is a qualitative concept． When quality index of power supply is used for quantitative description，the demand of different users for premium power supply is very different，and it is impossible for power supply enterprises to provide completely different power supply for each user． Therefore，it is a more feasible way to provide value － added services based on the demand categories of premium power supply． Firstly，the diversity demand of users for premium power supply and the service desire of power supply companies are studied，and the classification index system of power quality is put forward，including customer value index and power quality utility index，which depicts the power quality demand of customers． Secondly，based on the proposed index system and the importance of each index，a power supply quality demand category identification model for users is established with the combination of qualitative and quantitative methods to classify the user power supply quality categories，and a differentiated value － added service package for premium power supply is designed． Finally，the cost － benefit model of value － added service package is proposed to determine the value － added service content and calculate the value － added service price of a single customer． The case analysis proves the rationality and effectiveness of the proposed method，which provides a reference for power selling enterprises to attract new users and carry out differentiated value － added services．