In order to investigate the influence of high temperature to the dynamic characteristics of rock, tests were carried out on large diameter SHPB setup with siltstone having undergone high temperatures of 100℃, 200℃, 300℃ and 400℃. The curve of stress-strain, peak strength, failure strain and Young's modulus of specimens were compared before and after high temperatures. The results show that the peak strength, failure strain and Young's modulus of specimens were all decreased with the increasing of temperature, which may be related to the internal change of mineralogical composition under different high temperature and the redistribution of internal stress of specimen after high temperature. The results of interrelated study are helpful for better understanding the mechanical properties of rock in changing temperature field during deep excavation, and provide directional guidance for engineering practice.