A method of electric load modeling is developed for wide area power systems. The method uses the data from wide area measurement systems （WAMS） to establish an error index for evaluating the systematic behavior and synchronously estimate the parameters of multiload nodes. The specific steps are given

i.e.

determining the characteristic variables of loads

clustering the load nodes and the load parameters

developing the systematic index

and estimating the load parameters. The simulation results have validated the possibility of the multiload nodes modeling and the effectiveness of the methods proposed. Finally

some further research topics are recommended.