Abstract: The temperature field and the influence of electrode conduct electricity property and conduct heat property on the electrode tip temperature during spot welding aluminium alloy was studied by numerical simulation method. To study electrode tip temperature field which is the part of spot welding process temperature field the axisymmetric finite element model of mechanical, thermal and electrical coupled analysis was developed. The influence of electrode conduct electricity property and electrode conduct heat property on electrode tip temperature during spot welding aluminium alloy was studied by finite element analysis software ANSYS. The numerical simulation results show that the temperature of the contact surface center between the common electrode and the wokepiece is 548℃ at 17 ms which is Cu/Al alloying temperature, and 577℃ at 58 ms. But when electrode conduct electricity property and electrode conduct heat property increase by one times than the common electrode, the temperature of the contact surface center between common electrode and wokepiece is 488℃ at 57 ms and is lower than Cu/Al alloying temperature during spot welding process. The electrode conduct electricity property and conduct heat property greatly influence electrode tip temperature.