The mechanical properties of marble, limestone, and sandstone as well as the stress-strain curve, the varying characteristics of the peak strength, the peak strain and elastic modulus were studied by using the MTS810 Rock Mechanics Servo-controlled Testing System under the action of temperatures rang- ing from room temperature to 800℃ . Results show that (1) the peak strength and elastic modulus of marble fluctuate at the temperature from normal to 400 ℃ ; and they decrease gradually over 400℃ . (2) With the rise of the temperature, the peak strength and elastic modulus of limestone show downward trend from normal temperature to 200 ℃ ; have little change from 200 ℃ to 600 ℃; and decrease sharply over 600 ℃ . (3) The peak strength of sandstone shows a downward trend while a little change for elastic modulus at normal temperature to 200 ℃ ; and from 200 ℃ to 600 ℃ , the peak strength of sandstone in- creases while a little change for elastic modulus; the peak strength and elastic modulus decrease rap- idly at the temperature over 600 ℃ . (4) The peak strain of limestone shows little change at normal tem- perature to 600 ℃ , however, the peak strain increases rapidly over 600 ℃; and for marble and sandstone, the peak strain decreases with the rise of the temperature from normal temperature to 200℃ , the peak strain increases rapidly over 200℃. The result can provide valuable references for the rock engineering design at high temperature. The mechanical properties of marble, limestone, and sandstone as well as the stress-strain curve, the varying characteristics of the peak strength, the peak strain and elastic modulus were studied by using the MTS810 Rock Mechanics Servo-controlled Testing System under the action of the temperature rang- ing from room temperature to 800 ° C. Results show that (1) the peak strength and elastic modulus of marble fluctuate at the temperature from normal to 400 ° C .; and they decrease gradually over 400 ° C. (2) With the rise of the temperature, the peak strength and the elastic modulus of limestone show downward trend from normal temperature to 200 ° C; with little change from 200 ° C to 600 ° C .; and decrease sharply over 600 ° C. (3) The peak strength of sandstone shows a downward trend while a little change for elastic modulus at normal temperature to 200 ° C; and from 200 ° C to 600 ° C, the peak strength of sandstone in- creases while a little change for elastic modulus; h and elastic modulus decrease rap-idly at the temperature over 600 ° C. (4) The peak strain of limestone shows little change at normal tem- perature to 600 ° C, however, the peak strain increase rapidly over 600 ° C .; and for marble and sandstone, the peak strain decreases with the rise of the temperature from normal temperature to 200 ° C, the peak strain increases rapidly over 200 ° C. The result can provide valuable references for the rock engineering design at high temperature.