Abstract: Magnesium hydroxide was prepared with brine as raw material and lime milk as precipitator.Effects of technological conditions,such as reaction temperature,chelator amount,reducing agent amount,and reaction time,on iron removal process were investigated.By orthogonal experimental,the optimal operation conditions of iron removing technology were obtained,namely,reaction temperature of 40 ℃,chelator amount of 0.15 g,reducing agent amount of 0.10 g,and reaction time of 10 min.Mass fraction of iron of magnesium hydroxide under these conditions was reduced to below 5×10<SUP>-4</SUP>.Moreover,this technology applied in iron removal for inorganic powders,such as calcium carbonate,light magnesium carbonate,and kaolin,all achieved good results.