A Mo 2C and an alumina-supported Mo 2C catalysts were prepared and their catalytic performance for the direct decomposition of NO to N 2 and O 2 was evaluated in a continuous-flow microreactor. The structural properties of the catalysts have been studied using X-ray diffraction as well as BET surface area measurement. The results show that the bulk molybdenum carbide and the Mo 2C/Al 2O 3 catalysts exhibit an excellent catalytic activity for NO direct decomposition. There is a stronger interaction between the β-Mo 2C phase and γ-Al 2O 3 support in the Mo 2C/Al 2O 3 catalysts when Mo content is higher. It is suggested that the base sites of Mo 2C and Mo 2C/Al 2O 3 catalysts may have played an important role in catalyzing the decomposition of NO.