Abstract: The Earth's radiation belts are regions where high-energy charged particles congregate in near-Earth space. Given that high-energy particles in the radiation belts pose a severe threat to the safety of spacecraft in orbit and astronauts, it is of vital importance to gain a thorough understanding of the spatiotemporal dynamic evolution of radiation belt particles. Data assimilation method can effectively integrate satellite observations with numerical simulation results, thereby enabling the reconstruction of the spatiotemporal evolution process of radiation belt electrons. This paper systematically summarizes the research achievements in data assimilation modeling of the Earth's radiation belt electrons in recent years. First, we provide a detailed introduction to the three-dimensional data assimilative model of outer radiation belt electrons (TDAMORE), which is based on the Kalman filter method. Building on TDAMORE, further research on data assimilation modeling of radiation belt electrons is carried out using observational data from satellites of different orbital types, such as Van Allen Probes, Arase, and FY-4A. This assimilation model fully leverages the respective strengths of satellite observations and numerical models, successfully reconstructing the short-term and long-term dynamic evolution processes of electrons with different energies and pitch angles in the outer radiation belt region (L=3-7), as well as their response characteristics to geomagnetic activity. Based on the assimilation results, further research on predicting the flux of radiation belt electrons during geomagnetic storms is conducted, and the predictive performance of the model is evaluated. Finally, this paper discusses and looks ahead to the future development directions and potential application scenarios of radiation belt assimilation models.