Abstract: The effects of electron and proton radiation on the output characteristics of solar cells are studied quantitatively. First of all,it is confirmed that the output current voltage,I-V model of solar cells obtained by the author’s previous work is still suitable for solar cells irradiated by high-energy particles;Secondly,an equivalent resistance（Req）is defined by the output current voltage characteristic quantity of solar cells. The relationship between the energy conversion efficiency（PCE）and the equivalent resistance（Req）of solar cells is found by using the least square curve fitting method,and the relationship between the equivalent resistance（Req）of solar cells irradiated by electrons and protons and the radiation dose is explained quantitatively. Finally,the model is extended to describe the relationship between the external quantum efficiency,EQE,and the incident photon energy（hν）of solar cells. The fitting results show that the model is in good agreement with the experimental data. The correlation coefficient R between the theoretical and experimental results is greater than 0.98,and the average relative error is less than 3%.