The charging characteristics and microscopic mechanism of space electrons irradiated polymers are the basis for the study and protection of spacecraft polymer charging and discharging characteristics. Monte Carlo method is used to simulate the scattering process of space electrons, and the fast secondary electron model simulates the generation of secondary electrons. The finite difference method is used to solve the charge transport process of charge continuity equation, current density equation and Poisson equation. The capture process realizes the transmission process of space electrons through the equation based on the Poole-French effect. Based on the electronic scattering/transport synchronization model and combined with the geostationary earth orbit electronic spectrum distribution theoretical formula of the French National Aeronautics and Space Research Agency (ONERA) and the ground experimental method of the agency (SIRNE), a scattering model based on the electron spectrum distribution in geosynchronous orbit is established. The numerical simulation of the charging process of space electrons irradiated polymers is carried out. The space charge density, space potential, electric field distribution and the space potential of polymer sample under the irradiation of single- and multi-energy electrons in space environment are obtained. The relationship among charging characteristics, microscopic parameters and surface potential of the sample is clarified. The surface potential characteristics of space electrons irradiated polymer are consistent with the experimental results. The single energy charge potential and strength are higher than those of multi-energy electrons. When the charging reaches a steady state, the electron mobility is smaller (less than 10 ^–11cm ²·V ^–1·s ^–1), and the absolute value of the space potential is significantly enhanced with the decrease of the electron mobility. When the composite rate is large (greater than 10 ^–14cm ³·s ^–1), the absolute value of the spatial potential increases with recombination rate increasing. The study of the charging characteristics of space electrons is not comprehensive because only the mode of single-energy electron irradiation is taken into consideration. The research results are of great scientific significance and practical value for revealing the charging characteristics and microscopic mechanism of space electrons irradiated polymer and improving the research level of spacecraft charge and discharge fault mechanism.