Application of Cu-exchanged chabazite catalysts for Urea-SCR of NOx in diesel engines is limited to some extent by catalyst deactivation with hydrocarbons (HCs). In this work, catalytic activity of commercial Cu-SSZ-13 catalysts with or without propene for selective catalytic reduction of NO with ammonia (NH3-SCR) was tested, and results showed that the DeNO(x) activity was obviously inhibited in the whole temperatures, especially in medium temperatures. Furthermore, BET, NH3-TPD, NOx-TPD, and in situ DRIFTS were employed to elaborate the propene poisoning effects on Cu-SSZ-13 catalysts. In the low temperature ranges, the competitive adsorption process between NOx and C3H6 contributed to the deactivation of Cu-SSZ-13 catalysts. The presence of propene would inhibit the NOx adsorption and activation on the catalyst surface. In the medium temperature ranges, coke depositions were very critical for the deactivation of Cu-SSZ-13 catalysts. The active copper sites would be covered by the coke depositions, while the chabazite zeolite pores were also blocked by coke depositions. At higher temperatures above 450 degrees C, coke could be quickly removed and the catalysts could be regenerated in the presence of rich oxygen. (C) 2014 Elsevier B.V. All rights reserved.