Abstract: Based on the study of the properties,mineral composition of blast furnace sludge,five separation technologies were researched to recover iron and carbon concentrate in this paper.It was showed that recovery and grade of iron and carbon got in simple flotation and flotation-gravity technology were higher than which got form magnetic-flotation,magnetic-gravity-flotation separation and gravity-flotation technology.Iron recovery and carbon grade could reach 69.54% and 66.76% respectively,in the flow of flotation-gravity technology.For simple flotation,the best iron gradeand carbon recovery were got,which were 56.19% and 64.93%,respectively.Data in this paper could provide some references for the similar properties blast furnace sludge.