Model validation is a highly recommended practice that should be performed periodically since the system model is very important for ensuring reliable and economic power system operation. Currently, field data are used to validate a specific model or an entire system. An FNET-based model validation procedure is proposed in this paper. It uses wide-area measurements to correct the response found from simulations so that the simulation output is close to the measurement of system events. An example case is given which demonstrates the successful application of this method. Some general rules are also concluded for system-wide model validation based on FNET measurements.