Abstract: Variable measurement of rock damage is the groundwork in study on damage mechanism of rocks and the key issue to bring the rock damage theory into practice in rock engineering. In this paper, measurement techniques currently used at home and abroad are summarized and divided into two categories of structural measurement techniques and feature measurement techniques, including SEM analysis, CT detection, stress-strain measurement, sonic wave detection, acoustic emission monitoring and infrared radiation detection, etc. When selecting a detection technique, the coupled relationship between the damage and the related physical mechanics parameters should be considered carefully so as to make the parameters reflect the damage variable values. And in practical application, it is necessary to select the variable to be easily measured and the suitable measurement techniques in accordance with thermodynamic principles.