Abstract: This paper aims to examine the effect of cyclic variation of temperature on rock mechanical property. Altered rock are selected and rock mechanics test is carried out to examine the effect of different temperature circulating frequencies. Based on the analysis of experimental data, the function is established to describe the variation pattern of mechanical properties of altered rock by cyclic temperature. It is shown that the mechanical properties of the altered rocks are obviously weakened by temperature cycle effects. With the increase of temperature cycle times, the peak strength, elastic modulus and tensile strength are decreased and the Poisson's ratio is almost constant. As the degree of alteration and fragmentation increases, the degree of damage increases. For the cyclic temperature to the mechanical properties of rock the phenomenon is more obvious. After 20 times, the damage rates of tensile strength, peaky peak intensity and elastic modulus can reach 42.38%, 34.69% and 29.57% respectively. The variation of the mechanical parameters of the altered rock and the cumulative damage rate with the change of the temperature cycle times are all subject to the exponential distribution.