Study on distributed micro-grid-connecting control strategy has important implications for increasing the reliability of micro-grid-running. In terms of loop current that existed in distributed generation when micro-grid system is under island model, restrain link of reactive loop current is designed for improving droop control, constant power output that distributed generation is under grid-connecting model is realized through translating droop control curve, and on this basis, grid-connected presynchronization controller is designed for insuring there won’t be great shock current when grid is connected. At last, for restrain of constant loop current that micro-grid is under island model running, control of switching under micro-grid running model and constant power control after micro-grid is connected, this thesis carried out modeling and simulation on Matlab/Simulink platform, the results showed validity and availability of improved droop control method.