Abstract:[Objective] In order to reveal the structural change of feldspathic sandstone caused by thaw collapse, the mechanism of the freezing and thawing erosion of feldspathic sandstone was discussed. [Methods] Freezing-thawing tests were conducted using high-low temperature heat chamber H/GDWJS-100L with different moisture content, different freezing temperature and different dry densities. [Results] The amount of frost heave changed slightly when the moisture content of feldspathic sandstone was below 11%, while it increased significantly when the moisture content was over 11%. In the process of thawing, the initial thawing settlement moisture content was about 13%. When the moisture content was higher than 13%, thaw settlement occurred, otherwise, frost heave occurred. The maximum displacement of the feldspathic sandstone was closely related to dry density, the variation of maximal displacement was the least when dry density was 1.80 g/cm3. With the same moisture content and dry density, the maximum displacement of the feldspathic sandstone during melting increased with the decrease of temperature. [Conclusion] In the process of freezing-thawing, the displacement of feldspathic sandstone can cause the rearrangement of particles and the change of the pore characteristic, resulting in the structure change of feldspathic sandstone.