The removal of NOx in simulated flue gas was studied using urea/ potassium permanganate solution with different concentrations as absorbent. Experiments were carried out in a packed absorption reactor filled with steel pall rings at about 70°C. The effect of amount of urea, amount of potassium permanganate, effective height of absorption solution and addition of SO2 on denitrification efficiency was examined. The results show that a high removal efficiency of NOx can be attained using urea/ potassium permanganate solution process, In the solution of 5% urea and 600mg/L potassium permanganate, the removal efficency of NOx could be achieved 91.5%. Increasing the amount of potassium permanganate and the effective height of absorption solution could improve denitrification efficiency remarkably. Whereas, no obvious improvement in NOx removal efficiency was observed when increasing the amount of urea without potassium permanganate. The adding of SO2 resulted in a decline of denitrification efficiency.