The invention provides a power system loading and unloading method and relates to the power technology, in particular to a loading and unloading algorithm. The method includes the steps that firstly, the load of each power system is calculated; then, all obtained calculation results are subjected to domestication processing, and then domestication processing results are subjected to parameterization processing; finally, according to parameterization processing results, the priority of each power system is judged, and the power systems are unloaded to a cloud server in sequence according to the priority from big to small. By means of the power system loading and unloading method, the priority of the calculated load of each power system can be calculated, accordingly the unloading sequence of the cloud server is obtained, and it is ensured that load calculation of the power systems is conducted orderly.