The volatility and randomness of photovoltaic generation will cause the output power of high-penetration photovoltaic generation fluctuate randomly and then increase the burden of power grid frequency adjustment. At the same time, high-penetration photovoltaic generation access of power grid will replace some conventional units, further weakening the power grid frequency modulation capability. Aiming to the new challenge that high-penetration photovoltaic has obviously affected the stability of grid, firstly this paper analyzes how can the photovoltaic generation affect the frequency stability of power grid. Then it introduces the current technical route of photovoltaic frequency regulation. Finally, the problems needed to be further studied are prospected considering the development of power grid and new energy in China. This work is supported by Major Special Project of Gansu Province (No. 17ZD2GA010) and Science and Technology Project of State Grid Gansu Electric Power Company (No. 52272716000K).