To achieve the elastoplastic calculation of threedimensional reinforced concrete fiber beam element in ABAQUS software,using theuserdefined subroutine interface UMAT of the software implicit modules,based on the concrete constitutive theory,which combined by Mander pressure skeleton curve,Guo Zhenhai pressure loading and unloading rules and Teng Zhiming tension loading and unloading rules,and Stee 102 constitutive theory of Opeen SEES,uniaxial constitutive hysteretic models for concrete and steel rebar were developed for threedimensional fiber beam elements in ABAQUS software,then comparisons with the existing low cyclic loading test results were carried out.The results show that the userdefined material subroutines in ABAQUS software do well in simulating hysteretic behavior of the threedimensional reinforced concrete skeletal structures.