The temperature distribution in a crystallizer has important influence on the position and shape of solid-liquid interface during continuous unidirectional solidification. Based on the established three-dimensional physical model, simplified terms, specified material parameters in thermal and physical properties, boundary conditions, and the calculation method of heat convection of cooling water, the numerical simulation and analysis on steady-state temperature field for continuous unidirectional solidification of NiTi shape memory alloy wire billets were proceeded under the condition of different combined parameters using ANSYS finite-element software. The results indicate that the NiTi shape memory alloy completely solidifies in the crystallizer and the solid-liquid interface presents flat under the given model and various parameters, which meet the basic requirement of continuous unidirectional solidification.