Abstract: To solve the scheduling problems caused by the uncertainties of microgrids (MGs) and the power factor limitation of grid-connected MGs, an active-reactive power robust collaborative operation strategy considering the power factor constraint and uncertainties is proposed for the active distribution system with multi-microgrids. Firstly, considering the influence of grid-connected MG power factor constraint, the active and reactive power regulation characteristics of a microgrid based on the back-to-back converter are analyzed. Secondly, considering the MG uncertainties and the MG power factor constraint, an active-reactive power robust collaborative optimization operation model with a min-max-min structure is proposed. This model is transformed into a mixed integer second-order cone programming problem by the second-order cone relaxation method. Then, to solve the problem that the max-min problem can't be solved directly by using the KKT condition to dual because of 0-1 integer variables, a solving method is proposed based on the two-level column and constraint generation algorithm, and an acceleration strategy is given to ensure the rapid solution of the algorithm. Finally, the effectiveness and superiority of the proposed strategy are verified based on the modified IEEE-33 bus system with 3 MGs. Simulation results demonstrate that the proposed strategy can effectively ensure the MG power factors within the required range and minimize the system operation cost by coordinating the active and reactive power output of the active distribution system in the "worst" operation scenario.