Abstract: Based on the theoretically analysis of the space radiation effect on triple-junction galliumar senide（TJ-GaAs）solar cells,combined with the results of ground test results,the radiation shielding design of the space solar cell array is presented this paper. This design has been successfully applied to one satellite operating in inclined geosynchronous orbit（IGSO）and the on-orbit verification has been obtained. The natural attenuation law of solar cell array output power caused by radiation effects is calculated through the data analysis of satellite measured telemetry parameters covering 5 year life cycle. Compared with the ground design results,the accuracy of the mathematical model and the assigned parameters are verified,which is helpful for the design of space solar cell arrays for the satellites operating in the MEO and HEO.