Abstract: Study the correlation analysis of land subsidence, groundwater level and formation lithology based on the land subsidence monitoring data in recent fifty years, put forward that land subsidence in Xi'an is mainly controlled by the properties of rock and soil and water exploitation, and consider that sand and clay interbed structure is the internal reasons of ground subsidence, groundwater over exploitation is inducing factors of land subsidence, the two and the ground settlement are the specific high correlation. The susceptibility, distribution range and amount of land subsidence are jointly determined by thickness ratio of cohesive soil and underground water level dynamic. In this paper, a new method to study the mechanism of land subsidence is explored, which has a positive significance to master the law of ground subsidence development, predicting the development of land subsidence and effectively preventing and controlling land subsidence.