Herein, we report the function of Pd species in the Pd-added La0.7Sr0.3CoO3 perovskite for removal Of NOx (NO+NO2) in the lean-burn NOx traps (LNT) process. The addition of Pd significantly improves the De-NO activity of the perovskite-based catalysts. The Pd-supported catalyst has an excellent NOx removal efficiency of 90.4%, which is higher than the Pd-doped catalyst (74.4%) and pure La0.7Sr0.3CoO3 (51.6%). Our results show that the addition of Pd species enhances both the NOx desorption behaviors to regenerate the NOx storage sites and NOx reduction ability of the catalysts in the fuel-rich period, which induces the improved NOx trapping performance in the followed lean-burn period. These achievements result in the enhanced De-NOx activity of the Pd-added catalyst in the alternative NOx storage and reduction operations. Compared with the Pd-doped catalyst, the Pd-supported catalyst possesses the higher utilization efficiency of the Pd, thus exhibiting a higher catalytic activity.