The excavation and support problem of deep foundation pit is very interested by construction engineers with the development of the high buildings in cities and exploration utilization of the underground pace. Stability and economy are the most important problems in deep foundation pit support. This paper mainly studied on stability and economy of steel sheet pile support structure. The steel sheet pile support technique was fully introduced and analyzed here, using a combined method of theoretical guidance, calculation analysis, engineering application with finite element program simulation and market investigation.