Abstract: To address the issues of uneven cooperative benefit distribution among various stakeholders and high investment costs and low utilization rates of distributed energy storage within a multi-microgrid (MMG) during the collaborative operation process, a dual-layer energy trading strategy for shared energy storage and MMGs considering comprehensive impact factors is proposed. Firstly, the cooperative game is embedded within the master-slave game between shared energy storage providers and MMGs, thereby establishing a dual-layer game-theoretic operational model. Secondly, by utilizing Nash bargaining theory, the cooperative game within MMG alliances is resolved, and an ideal benefit allocation model considering the comprehensive impact degree is proposed. The cooperative contributions of each member are evaluated based on the electricity impact factor and carbon emission impact factor. The benefits are subsequently allocated in a fair manner according to the comprehensive impact degree, thus ensuring effective energy cooperation. Finally, a hybrid solution method that combines the improved particle swarm algorithm with the alternating direction method of multipliers (ADMM) algorithm is proposed, and the Yalmip toolbox and Mosek solver of the MATLAB platform are used to obtain the solution. The effectiveness of the proposed model and method is verified through case simulations.