Abstract: In order to study the NH3 modification affected to the denitrification performances of the activated coke, NH3/H2O with different volume fraction was app lied as the activator to prepare a series of activated coke.The X-ray photoelectron spectroscopy was applied to characterize the surface chemical properties of activate d coke.A NO removal experiment with activated coke and the NH3 adsorption volume experiment were conducted on the fixed bed reaction device under the condition 0 f the temperature of 150 °C.The results showed that the NH3 modification added could increase the surface 0 element content and N element content of the activated C oke and could remarkably improve the denitrfication efficiency of the activated coke. The higher NH3 adsorption volume of the activated coke, the higher denitrification efficiency would be.The experiment results confirmed that NH3 adsorption to activated coke would be the key step affected to the selective catalysis reduction denitrific ation reaction.