The CuO/$3AL_2O_3{cdot}2SiO_2$ catalyst impregnated ceramic candle filters for nitrogen oxides removal were prepared by porous mullite($3AL_2O_3{cdot}2SiO_2$) support and CuO catalyst deposited on this support to achieve uniformly dispersed CuO deposition, which are impregnated into the pores of available alumino-silicate ceramic candle filter. The CuO/3$AL_2O_3{cdot}2SiO_2$ catalyst impregnated ceramic candle filters were characterized by XRD, BET, air permeability, pore size, SEM and catalytic tests in the reduction of NOx by NH$_3$. The observed effects of CuO/3$AL_2O_3{cdot}2SiO_2$ impregnated ceramic candle filters in SCR reaction are as follows : (1) when the content of CuO catalyst increased further, activity of NO increased. (2) NO conversion at first increased with temperature and then decreased at high temperatures (above 40$0^{circ}C$), possibly due to the occurrence of the ammonia oxidation reaction. (3) In pilot plant test for 3 months, NO conversion was greater than 90%.