The groundwater that has influence on the construction of the project in Xi'an is phreatic water, and its water level is mainly affected by the landform, water bearing stratum, meteorology, surface water system, surface water body, urban ecological water supplement and the precipitation of adjacent projects. Combined with engineering examples, the difference of the annual variation of groundwater level in different geomorphic units is put forward. At present, the groundwater is still in the overall slow rising period. The conclusion can provide the basis for anti-floating water level determination in the construction site.