Abstract: It was performed nonlinear finite element analysis for K shape eccentrically braced steel frames on differentlength of link beam. Analysis indicates that the strength, rigidity, ductility and energy -dissipation performance of K shapeeccentrically braced steel frames deteriorate differently with the length increase of link beam. The shorter the link beam is,the larger plastic deformation of it, so itmakes plastic collapse easily, while a long link beam has a poor cyclic behavior. Atthe end of this paper, suggestions on design of the length of link beam based on finite element simulation results arepresented.