Abstract: This paper discusses the magneto-increasing technology used in hematite roasting. It is realzed bysetting the magneto-increasing section in reducing zone of shaft furnce and inputting adequate amountof magneto-incrasing agent. The agent is mixed with water-vpour an coke-oven gas. Therefore, thedetermination of amount of water-vapour generation and coke-oven gas is the technical tast solved inthis paper.