Aiming at dispatching the distributed generation reasonably to make the microgrid operate economically and reliably, a method based on co-evolutionary genetic algorithm is proposed to dispatch the distributed generation in microgrid. A dispatching model of economic and environmental CCHP microgrid system is established. The new consideration of hot standby constraint is added. Multistage objective function is established, and the virtual charging and discharging price of the battery are included in the population optimization objective function. Combined with co-evolutionary genetic algorithm, the population optimization objective function and the elite optimization objective function are used to seek the best individuals from the population. The dispatching policies in grid-connected operation and isolated-connected operation are given. The analysis of the results of economic dispatch in winter in two modes of grid-connected operation and isolated-connected operation validates the effectiveness of proposed dispatching mode and the algorithm.