Abstract: There are usually only three types of nodes,viz,the slack node,active power-voltage node and active power-reactive power node in the traditional power flow calculation based on Newton-Raphson method.So it is difficult to calculate the power flow of microgrid with droop controlled distributed generators using the traditional Newton-Raphson method directly.A novel power flow calculation method similar to Benders decomposition is proposed.The power flow calculation of islanded microgrid under decentralized droop control strategy is decomposed into a traditional Newton-Raphson power flow calculation subproblem and a droop control node updating sub-problem,while solving the original problem via the alternative iteration of two sub-problems.In this algorithm,the complex original problem is decomposed into two simple sub-problems,which makes solving the original problem efficient and fast.By the simulation tests on case studies,the feasibility and validity of the proposed methodology are proved.