Abstract:Testing study is made on the mechanical properties of granite after undergoing different high temperatures. The mechanical properties include stress-strain curve,peak stress,peak strain,modulus of elasticity and Poisson’s ratio of granite. The results show that the temperature does not obviously affect the mechanical properties of granite in the temperature ranging from room temperature to 400 ℃. But the mechanical properties deteriorate rapidly with the increase of temperature when the temperature is above 400 ℃. In this case,the peak stress or the strength and modulus of elasticity decrease rapidly,the peak strain increases rapidly,and the Poisson’s ratio presents a tendency of decreasing as the temperature increases.