Processing an ultra-stable cavity using ultra-low-expansion (ULE) material with an ultra-low coefficient of thermal expansion and controlling its temperature at the zero-thermal-expansion is the key to obtain a low-frequency drift rate. The measurement of the zero-thermal-expansion temperature of the ultra-stable cavity plays a key role in the research field of ultra-stable lasers. The ultra-stable laser with a low drift rate at the zero-thermal-expansion temperature is of great significance for the precise measurement of the energy level transition spectral lines. This paper expounds the basic principle of PDH (Pound-Drever-Hall) laser frequency stabilization based on an ultra-stable cavity, introduces the methods to measure the important specifications of an ultra-stable laser, and introduces in details the three methods to measure the zero-thermal-expansion temperature of the ultra-stable cavity, including reference cavity beat frequency method, femtosecond optical comb measurement method, and the optical clock measurement method. Then the paper analyzes their operating conditions and working principles, and completes the experimental verifications. Finally, the paper summarizes and prospects the future development direction of the precision measurements of zero-thermal-expansion temperature. It provides a reference for the further development of the ultra-stable laser technology.