Abstract: <SPAN lang=EN-US>Magnesium hydroxide was applied in industrial wastewater treatment in foreign countries in recent years and it showed excellent decoloring effect because of its characteristics of buffering,large activity,strong adsorption capacity,</SPAN><SPAN lang=EN-US>non-corrosion,</SPAN><SPAN lang=EN-US>safety,and non-toxicity etc..The treatment of dyeing wastewater with magnesium hydroxide produced from brine was mainly studied.The results showed that magnesium hydroxide had good effect for decoloring and suspended substance removal,meanwhile,removal rate of chemical oxygen demand was also quite high.<BR></SPAN>