The power-sharing accuracy, system stability and transient performance can be seriously influenced by the unbalanced complex impedance, the complicated location of power generations and loads in microgrid. The control strategy of autonomous microgrid based on coordinate rotational virtual impedance is proposed to handle this problem. The coordinate rotational virtual impedance loop is adopted to improve the impedance characteristic. The system power-sharing is implemented by voltage magnitude and frequency based droop control strategy. The system stability and transient performance is ensured by the outer voltage control loop and inner current control loop with feed-forward compensation. In order to analyze the effect of coordinate rotational virtual impedance on the performance of microgrid, the small-signal dynamic model of whole microgrid is built. The simulation results verify the accuracy of small-signal dynamic modeling and analysis, confirming that the proposed control strategy can improve the active and reactive power decoupling, the power sharing accuracy, and the system stability and transient performance.