Abstract： Comprehensive NOx storage/reduction (NSR) experiments were conducted in a quartz flow reactor to investigate the influence of regeneration period, temperature and volume fraction of reductant on NSR performance of Pt/Ba/Ce/γAl2O3 when H2 was used as a reducing agent. It is found that the highest conversion ratio in the optimum regeneration time can be obtained, and it is dependent on the temperature and the volume fraction of the reducing agent. As the temperature increases,  the optimum regeneration time increases. As the volume fraction of the reducing agent increases, the optimum regeneration time decreases.