Abstract: Along with the fast pace of urbanization,the protection of historic buildings draw lots of attention in the city. Deep soil excavation engineering in the city will inevitably affect the surrounding historic buildings.Combined with the Tianjin area deep excavation engineering examples,this paper analyzed the failure mechanism and considered uneven subsidence is an important reason.Also,according to the monitoring results,The author analyzed the deformation law in Tianjin region,and discussed the measures to decrease the building deformation.The results can provide a reference for other similar projects.