Reasonable coordination between micro-source and load is the theoretical basis of security and economic operation for micro-grid. Based on the analysis of the distributed generation cost and controllable load characteristic, this paper establishes the objective function with lowest operating cost of two time domains. With the constraints such as the balance of active power of micogrids, the upper-lower limits of distributed generation output, creep speed and the electricity utilization characteristics of controllable loads, it establishes security and economic dispatch mathematical model of source/load for micro-grid. The optimization strategy is formulated with the principle of giving priority to the use of renewable energy and the cost minimum. Tabu search is used to solve the dispatch model of micro-grid and the dispatch plan of micro-grid source/load is gained. Finally, the global optimal result is compared with that of simplex method. The example analysis indicates that the dispatch scheme based on Tabu search algorithm is close to global optimal solution. The dispatch scheme result of 24-hour scheduling cycle is similar to that of 1-hour scheduling cycle. This work is supported by National Natural Science Foundation of China (No. 51477184).