Abstract: In order to analyze the influence of various factors on borehole shrinkage of expansive mudstone in coal mine, the sensitivity analysis of the influence of various factors on borehole shrinkage of expansive mudstone was carried out by using numerical software ANSYS, with water content, crustal stress and different mechanical parameters of surrounding rock. Sensitivity factor was introduced to evaluate the sensitivity of each factor to the effect of borehole shrinkage, and the sensitivity of each factor was analyzed by orthogonal experiment. The experiment results show that water content is the most sensitive and important parameter affecting the borehole shrinkage of expansive mudstone; the influence of linear expansion coefficient and poisson ratio on borehole shrinkage is significant, but the effect is less than that of water content; the effect of elastic modulus is relatively small; the influence of crustal stress is the least significant.