Abstract: The alternating direction implicit finite difference method is used for two-dimensional axis symmetry numerical simulation of transient temperature field in friction welded joint of 0.35 per cent carbon tubular steel.The thermal cycle in some zones of friction welded joint i n which thermocouples be easily used was automatically measured by meams of computer real-time sampling.The results have shown that the mathematical mode founded and the calculating result are reasonable and helpful to determine correct welding specification.