As an important part of the spacecraft power system, solar cells require high conversion efficiency and reliability and a longer service life. By using an anti-irradiation glass coverslip, the protection of the solar cell against particle radiation can be enhanced, the service life of the solar cell can be prolonged, and the spacecraft can obtain a reliable energy supply. Borosilicate glass is an ideal glass cover material for solar cells. In this paper, Monte Carlo method is combined with SRIM software to study the physical mechanism of damage of proton irradiated borosilicate glass. Combining the theory of particles-matters interaction with the basic formula, based on analyzing the stopping power, ionization energy loss and displacement energy loss of protons in different borosilicate glass, and the generation of vacancies, the physical mechanism of the damage was analyzed. The results show that the proton irradiation damage with energy of 30?120 keV mainly occurs on the surface of borosilicate glass; proton deposition and vacancies distribution follow the Bragg curve; ionization energy loss is the main part of energy loss, which increases with the increase of incident energy, leading to ionization and excitation of electrons; displacement energy loss increases with the decrease of energy in the glass, which leads to the vacancy defects of boron, oxygen and silicon. Ionization effect and defects are important reasons for the formation of color center in borosilicate glass.