To improve the removal capacity of NO + O2 effectively,the alkaline earth metal-doped order mesoporous carbon (A-C-FDU-15(0.001) (A =Mg,Ca,Sr and Ba)) and Mg-C-FDU-15(x)(x =0.001-0.003) samples were prepared,and their physicochemical and NO + O2 adsorption properties were determined by means of various techniques.The results show that the sequence in (NO + O2) adsorption performance was as follows: Mg-C-FDU-15(0.001)(93.2 mg/g) ＞ Ca-C-FDU-15(0.001) (82.2 mg/g) ＞ Sr-C-FDU-15(0.001) (76.1 mg/g) ＞ Ba-C-FDU-15(0.001) (72.9 mg/g) ＞ C-FDU-15 (67.1 mg/g).Among all of the A-C-FDU-15(0.001) samples,Mg-C-FDU-15(0.001) possessed the highest (NO + O2) adsorption capacity (106.2 mg/g).The species of alkaline earth metals and basic sites were important factors determining the adsorption of NO + O2 on the A-C-FDU-15(x) samples,and (NO + O2) adsorption on the samples was mainly chemical adsorption.Combined with the results of (NO + O2)-temperatureprogrammed desorption ((NO + O2)-TPD) and in situ diffused reflectance infrared Fourier transform spectroscopy (DRIFTS) characterization,we deduced that there were two main pathways of (NO + O2) adsorption: one was first the conversion of NO and O2 to NO2 and then part of NO2 was converted to NO2-and NO3-;and the other was the direct oxidation of NO to NO2-and NO3-.