This study focused on the low-cost denitrification and demercuration from the sintering flue gas,sawdust was chosen to obtain bio-char under the slow low-temperature pyrolysis(from room temperature to 600℃ ,5℃ /min).Then,the bio-char was modified by the impregnation of ni-tric acid.At last,the modified bio-char finally was applied to carry out the experiments of denitrifica-tion and demercuration in a fixed-bed equipment.Compared with the bio-char,the modified bio-char made a better performance on the denitrification and demercuration of simulative flue gas.Moreo-ver,it was showed that modified bio-char has a lager specific surface area and microporous than that of bio-char by the analyses of Specific surface area(BET)and Infrared Fourier spectrum(FT-IR).The bio-char was modified to increase a number of oxygen-containing functional and alkaline atomic groups.The modified bio-char resulted to exhibit significance capacity on the removal of nitric oxide and mercury under the comprehensive effect of the two factors.