The LaMnO3-based perovskite-type mixed oxides were studied for both trapping of NOx and combustion of diesel soot. The LaMn0.7Ni0.3O3 (LMN3) perovskite shows high NOx adsorption capacity, quick adsorption rate and efficient adsorbed species. After the catalyst interacts with NO at low temperature around 325 degrees C, decomposition of the nitrates leads to the decrease of the maximum soot oxidation temperature to 430 degrees C. The fine crystallite size, increased surface area and readily reducibility at low temperature also favor the oxidation of soot over LMN3 under loose contact conditions.