| Xi'an ground fissures' damage to the constructions has been found since the Fifties of last century. Nowadays, 14 ground fissures have been found in Xi'an area, and ground fissures have been the main environment geological disaster in Xi'an city. The research on the development condition, section structure characteristic and activity of Xi'an ground fissures, not only could be the precondition and base of a deeper study on the fissures, but also could help people know the new trends and characteristics of the fissures so that they can make a much better layout of Xi'an city planning.This paper drew xi'an ground fissures' strip-chart including the single ground fissure's plane distribution, engineering geological section plans, exploratory trench profile chart and photos of ground fissure, and do some research on the development characteristic of xi'an ground fissures synthetically. Ground fissure in Xi'an go along with the loess foothill at NEE, consistent with Lintong-Chang'an fault. The fissures extend to the two ends along the line of strike. Secondary fissures lie in the south of the main fissures and the dip of them is opposite to the main fissures. The displacement of fault in the same stratum increases with the depth, having many characteristics of growth fault. The typical combination modality of the main and secondary fissures reflects indirectly the characteristic of stress field which fissures lie in. The fissures' activity intensity weakens with the decrease of excessively pumping ground water, and shows many tectonic fissure activity features. On the whole, the activity intensity is still stronger on the east part of the city than the west part and stronger on the south part of the city than the north part. In these aspects cited above, ground fissures in Xi'an show strong regularity. Apparently, their growth and distribution are controlled by the action of region structure and over-extraction of water underground is the major reason for strong action intensity.
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