Abstract: In recent years, China has perfected the executive mode of two-part electricity price policy by increasing users’ options. This paper uses the social welfare model to analyze the impact of the implementation of the national adjustment two-part electricity price system on the efficiency of market resource allocation in the year of 2016. Results show that the relaxation of the change cycle of the two-part pricing system can reduce the basic electricity price burden of enterprises, who have stopped production or half stopped production. However, it is not beneficial to the efficient production enterprises, which is not conducive to promoting the survival of the fittest in enterprises as a whole, and reduces the long-term utility of the whole society. The empirical results also show that The change of the two-part electricity price policy led to the decline of the total social welfare, which was reflected in the drop of the load rate by 7%. Meanwhile, it also reduces the fairness among users, which is reflected in the capacity utilization rate dropping by 30.6%. We believe that simply adjusting the executive mode of the electricity price policy is not conducive to the optimal allocation of power resources, and all enterprises should adopt the fair electricity price policy at the same time.