Abstract: Based on the analysis of thermo-elastic-plastic effect, the surface temperature of Q235 steel during tensile tests was measured by using an infrared camera. Both the surface temperature field and it versus time for different strain rate were obtained. The true stress and true strain curve was determined, and this curve was used as the constitutive equations of Q235 steel. A numerical procedure was devised to model the thermoplastic effect during the tensile tests by using ANSYS software, and the influence of the strain rate, coefficient and heat-transfer coefficient on the surface temperature were studied. The results show that the heat loss during deformation process will be smaller as the strain rate increase, and the temperature increase on the specimen surface generated by the plastic deformation will be higher. The temperature rise at the middle of specimen near the necking area is maximum, while it declines towards the end of specimen from the necking area. It is concluded that the larger and more concentrative plastic deformation of specimen happens at the same time, the much higher temperature rise can be obtained. The simulation results show that it is a good way to analyse the thermoplastic effect by the commercial finite element software. Smaller as the strain rate increase, and the temperature increase on the specimen surface generated by the plastic deformation will be higher. The temperature rise at the middle of specimen near the necking area was maximum, while it declined towards the end of specimen from the necking area. It is concluded that the larger and more concentrative plastic deformation of specimen happened at the same time, the much higher temperature rise could be obtained. The simulation results matched well with the experiment results showed that it was a good way to analyse the thermoplastic effect by the commercial finite element software.