Abstract: The function of the visualization of radiation field in the reactor cabin and simulation calculation of human body absorbed radiation dose is developed based on the DELMIA software. The reactor cabin radiation intensity distribution is displayed visually by radiation field visualization, which can assist the work of personnel maintenance, reduce the radiation dose of the staff, and improve the work efficiency. Through the simulation calculation of the human body absorbed radiation dose, the human body damage degree can be understood, so as to provide the necessary radiation protection measures for the maintenance staff. Based on the analysis of statistical reports output, the maintenance process can be evaluated and optimized, and this plays an important role in the actual reactor maintenance engineering. The calculation result is fast and real-time, and the display effect is good.