Deep high-temperature rock is often subjected to different cooling ways under both artificial and natural factors, and the deterioration of its mechanical properties has an important impact on all kinds of underground engineering. Based on the two cooling ways, natural cooling and water cooling, the changes of physical parameters and longitudinal wave velocity before and after cooling as well as the characteristics of Brazilian tension after cooling of different heat-treated granites, were studied. The results show that: when the heat treatment temperature is between 25-200 ℃, the effect of cooling ways on the physical properties, longitudinal wave velocity and the deformation and strength characteristics of Brazilian tension is not obvious. With the further increase of the heat treatment temperature, the decay rate of each test parameter is also increasing, and the decay rate of the above parameters of the samples is further aggravated in the way of water cooling. The longitudinal wave velocity can better reflect the internal damage of the samples. Based on the decrease of the wave velocity, the damage factor of the sample can be determined, which can be directly used to estimate the tension strength of the sample after different heat treatment methods.