The mechanical properties of marble were studied using the MTS810 Rock Mechanics servo-controlled testing system at temperatures up to 800°C. This was done to analyze the stress-strain curve, peak stress, peak strain, and modulus of elasticity of marble. The results show that the peak stress and elastic modulus decrease with increasing temperatures, and the rock mechanical strength decreases suddenly in certain temperature ranges while the peak strain increases stepwise as the temperature rises. Marble ductility increased greatly at 800°C. The strain increases slowly as temperature rises after the peak stress occurs, but brittle fracturing is the main destructive manner of marble. The results also reflect the fundamental regulation of interior structural change in sandstone at different temperatures, providing a reference for rock engineering design.