In this paper a new scenario-based approach is proposed to design optimized multiple-microgrids considering the uncertainty of load consumption and renewable DGs generation. The proposed method is used to determine the optimal capacity, type, number and location of renewable and controllable distributed generation resources along with the switch optimal location to cluster the traditional distribution network into a set of interconnected microgrids with economic and reliable structured. This study aims to decrease the total design costs including investment and operation costs, system loss cost, air pollution cost as well as the microgrids energy not supplied cost. Different considered objective functions have been modeled using weighted coefficients method as a singleobjective nonlinear mixed integer problem. In addition, the uncertainty of the problem input parameters is modeled using scenario generation method, and in order to decrease the computational burden and increase the program execution speed, the backward scenario reduction technique is used. The Cuckoo optimization algorithm is used to optimize the objective function, and also the effect of optimization coefficients on the design problem and the robustness of the proposed algorithm are investigated using sensitivity analysis. Finally, the efficiency and performance of the proposed method are evaluated on the standard 33-bus network and the results show that the proposed method is an effective tool to design interconnected microgrids with consideration of uncertainty.