Abstract: The adsorption of methyl orange in dye wastewater using activated clay is studied. The effects of contact time，dosage of activated clay，pH value and temperature on the adsorption are investigated.The relaled thermodynamic parrameters of the adsorption of white clay to methyl orange are obtained , indicating that the adsorption process of activated white clay to methyl orange is a spontaneous process，and high temperature is not conducive to adsorption.

Key words: ａｃｔｉｖａｔｅｄ ｃｌａｙ, ｍｅｔｈｙｌ ｏｒａｎｇｅ, ａｄｓｏｒｐｔｉｏｎ, ｔｈｅｒｍｏｄｙｎａｍｉｃ ｐａｒａｍｅｔｅｒｓ