BaO(s1) was used as the first adsorption sites, and Pt (s2) was used as the second adsorption site, the micro-reaction kinetics simulation of NOx and PM in diesel engine by adsorber-reduction catalyst was calculated with the software of Chekmin. The results showed that in lean burn condition, gas phase NO(g), NO2(g) were stored in forms of NO2 (s1), NO2NO3 (s1), and NO3 (s1) on the surface of BaO, but in rich burn condition, N atoms in NOx desorption from surface of BaO combined with each other to form N2 molecular. Surface reaction was occurred between C (S) and reactive oxygen species O*. The absolute time, the ratio values of lean burn condition, exhaust temperature and oxygen concentration in diesel engine exhaust pipe have a great impact on removal of NOx and PM emission.