The geotemperature field of upper crust in Tianshui earthquake area is calculated by using finite element method. The results show that basement and fault structures are main factors affec ting shallow geotemperature field in this area.Qilian fold system is a high geothermal anomaly area, whereas Qinling fold system, low geothermal anomaly area. And the fault zone along the north edge of West Qinling mountains is a zone with high geothermal gradient.It is considered that the occurrence of historical earthquakes in this zone is related to thermal stress difference.