Renewable energy generation is widely used to solve energy shortage and environment problems. Since the output power of the solar cell and the wind turbine will change with the sunlight irradiation and the wind flow, the power of the solar cell and the wind turbine are not stable; therefore, there is a need for storage equipment connected to the micro-grid system. With the characteristics of high-efficiency energy storage and quick response to power exchange, the superconducting magnetic energy storage (SMES) can be used to meet the balance requirements of the micro-grid. This paper proposes an improved control strategy combining SMES and micro-grid. An SMES and micro-grid system are connected together with the AC bus. A detailed model of the hybrid system is built with MATLAB/SIMULINK. Simulation results with and without SMES connected to the grid-connected photovoltaic system are presented, compared, and analyzed. The simulation results demonstrate that the SMES system can maintain the grid-side power as a constant value, which contributes to the stability and reliability of the micro-grid system.