Electron beam selective melting parts experienced complex thermal history, resulting in multi-scale microstructure. Thermal history data play an important role in analyzing microstructure formation. The complex metallurgical behavior of micro-melting pool makes it difficult to obtain the temperature-time-spatial data by experimental means. As a new technical means, numerical simulation technology provides a new idea for solving this problem. In this paper, the research status of numerical simulation of electron beam selective melting thermal behavior is reviewed from the aspects of mathematical theory of temperature field, simulation process, thermal-mechanical coupling simulation, thermodynamic simulation of molten pool and thermal defect mechanism. The challenges and future prospects of numerical simulation of electron beam selective melting thermal behavior are discussed.