Abstract: With the development of the electricity markets, microgrids, as one market player on the demand side, must also purchase electricity through the electricity markets. Subject to market bidding rules and considering the risks brought about by the uncertainty of clearing prices, the independent bidding of a single microgrid will pay a high expected cost. Compared with independent bidding, joint bidding can effectively reduce costs by expanding the scheduling space of microgrids through mutual aid between different microgrids. The so-called joint bidding means that multiple microgrids without electrical connection form a joint bidding entity to report the bidding curves and purchase electricity in the electricity market. Second, considering the uncertainty of market clearing, a bidding model is established based on typical electricity price scenarios of the day-ahead market. Finally, due to privacy protection, the enhanced Benders decomposition, which is suitable for mixed integer sub-problems, is used to solve the bidding model in a distributed manner. The simulation results show that the joint bidding strategy proposed in this paper reduces the cost compared with independent bidding, and the distributed solution does not affect the optimality of the results.