Abstract: In the deregulated electricity market environment, the power trading can be carried out among the operators in the micro-grids. In this paper, we take the cost of individual transactions between operators in a micro-grid and power distribution network as the disagreement point of bargaining, and propose a day-ahead economic dispatching Nash bargaining method for multi-operators in micro-grids based on Nash cooperative game theory. This method can minimize the cost of micro-grid systems while each operator obtains Pareto optimal cost. The Nash bargaining model based on this method is a non-convex and non-linear model, which is not easy to solve directly. This paper decomposes the Nash bargaining model into two convex sub-models and uses ADMM algorithm to solve them sequentially in order to protect the privacy of operators. The simulation gives the cost comparison of each operation agent in the micro-grids before and after the bargaining, and further analyses the Nash bargaining strategy among multi-operators in the island mode.