Abstract: Charge coupled device (CCD) image sensors, as crucial photoelectric imaging devices, are widely employed in fields such as astronomical observations, medical imaging, aerospace, and industrial inspections. Due to the complex space environment beyond Earth’s atmosphere, CCD image sensors used in aerospace equipment are susceptible to radiation damage, including displacement damage, total ionizing dose (TID), and single-event effects (SEEs), which can degrade imaging performance, and in severe cases, lead to device failure. However, current research on radiation damage to CCD sensors primarily focuses on experimental irradiation and analysis, with relatively few simulation studies. Thus, there is an urgent need for simulation studies under varying irradiation conditions to explore the relationship between SEEs and the sudden changes in electron concentration at the moment of incidence within the pixel regions. During normal operation, CCD image sensors experience several key time points, such as before the potential well formation (T₁), after potential well formation (T₂), and during charge packet transfer (T₃). At these different stages, heavy ions can influence the electron density and electrostatic potential distribution within the pixel unit. Therefore, by comparing the electron density and potential distribution before and after irradiation, as well as examining the curves that vary with incident time and position, deeper insights into the impact of radiation on the performance of CCD image sensors can be obtained. In this study, different single heavy ions were incident on various transfer gates in the photosensitive region of different CCD image sensors at the T₁, T₂, and T₃ intervals. Transient changes were observed at time points such as 10, 20, and 30 ps after incidence. The impact of single-particle incidence on the electron concentration and potential distribution in the pixel region of CCD image sensors was investigated at various sensitive moments and linear energy transfers (LETs). By developing physical models of the CCD pixel structure and single-particle radiation damage effects, simulations of transient changes in dark current, potential, and electron concentration during different operational stages (reset, transfer, and storage of photogenerated charges) were conducted. The results show that the charge collection (T₂) and charge transfer (T₃) stages are more susceptible to single-event transient effects. As LET increases, the depletion region of the pixel’s potential well is disrupted. While different incidence positions have negligible effects on the potential well region, they significantly impact the photoconductive charge collection region. This simulation study provides theoretical insights into the mechanisms of SEEs in CCD image sensors at the pixel level.