In this work we had presented a power system electricity frequency control approach of 100% renewable energy sources isolated power grid by applying model predictive control (MPC). As the PV panel and storage battery price had dramatically dropped in these years, large capacity of PV generation and storage battery had been introduced base on an original 100% renewable energy power system. MPCs had been design for each of the model (Photovoltaic Generation, Wind turbine Generation, Storage Battery, Fuel Cell and Seawater Electrolyzer) to suppress the consumption and generation balance. In addition, in order to suppress the load frequency, demand response (real-time pricing) also had been applied in this scheme by adjust the controllable loads. All of the control approach proposed in this work had been verified by Matlab@/Simulink@. And by discuss and analysis the simulation results, the stability, robustness, reliability and effectiveness of this scheme had been examined.