Abstract: A mathematical model of the electromagnetic suspension continuous casting process for AZ31 magnesium alloy billets had been built up using Microsoft Visual C++ 6.0 software and finite difference method (FDM).The temperature field during electromagnetic suspension continuous casting of magnesium billets was simulated by the model and compared with the actual measured temperature.The results show that the model could be used to simulate the actual casting process.The initial temperature of the suspension casting alloy declined,cooling speed increased and solidifying time of billets shortened with increasing the content of suspension particles(20%ZrB2+80%AZ31).