Abstract: According to performance experiment of partially restrained steel frame with RC infill walls(PSRCW),the overstrength behavior has been analyzed,and ductility reduction factors of PSRCW is proposed based on equal collapse rule.Rμ-μ-T empirical formula from Newmark-Hall was used to deduce ductility and strength reduction factors of PSRCW under the rare level of earthquake.In order to make the research be consistent with seismic code,this paper also gives ductility and strength reduction factors of PSRCW under the moderate level of earthquake.These suggestions can provide references for reasonable design of PSRCW.