Aiming at the problems of low correlation between carbon metering scheme and users' electricity transaction, and poor coordination between carbon emission responsibility and users' electricity consumption behavior in power system, a low carbon economy optimization model of power system based on carbon emission flow was proposed. First of all, the carbon emission flow theory was used to accurately calculate the dynamic load carbon potential between power user nodes, and deeply integrated the relationship between load carbon potential and user behavior, so as to effectively improved the low carbon regulation ability of node power consumption behavior. Secondly, the carbon responsibility sharing method of each user node was put forward by using Shapley method, and the carbon quota of each user node was deduced, combined with the principle of ladder electricity price, which made the carbon emission responsibility interval of each user node more reasonable. Thirdly, the highest emission reduction of the system and the lowest carbon cost of the node were selected as the objective function to establish the low carbon economy optimization model of the system, and the benefit analysis scheme for the optimization results was put forward. Finally, the analysis of the example shows that the proposed model not only meets the goal of low carbon demand of the power system, but also achieves the positive effect of optimizing the electricity consumption behavior of users, and realizes the two-way constraint of reducing carbon and improving electricity consumption of the system. It provides a feasible scheme for low carbon economic operation of power system.