Abstract: The nonlinear three-dimensional finite element analysis of five through-beam-type interior RCS beam-column connections is performed by the finite element software ANSYS and the analytical results are compared with experimental results. The effect of material nonlinear constitutive relations and concrete cracking and crushing is all taken into account. A series of numerical simulation technologies is studied, such as selecting element type, defining material model of steel and concrete, establishing global finite element model with discrete reinforced bars elements and stirrups elements, applying loads to the specimens, and setting solution controls option and solving. The investigation shows that ANSYS finite element software may simulate the behavior of RCS beam-column connections under static loading through reasonably selecting parameters, and the analytical results agree well with experimental ones.