Abstract: :Failure of fastener-style tubular steel formwork is one of the key issues faced in safe construction at present.In order to provide the basis for the working-out Technical Rule for Steel Tubular Formwork Support with Couplers in Building Construction, a calculation model for construction system of fastener-style steel tubular formwork support was founded by means of software ANSYS and sensitivity analysis of main parameters that dominate the ultimate capacity was conducted. Relative sensitivity curves were obtained, which supply a reliable basis for erecting fastener-style steel tubular formwork support.