Power plants that emit great amounts of nitrogen oxides are the key total mass control part of the “Twelfth Five-Year Plan”. SCR is widely used because the technology is mature and the denitrification efficiency is high. According to the problems of the application of SCR, this paper puts forward relevant suggestions: 1) Combine different flue gas denitrification technologies to raise the denitrification efficiency. 2) Urea is recommended as the reductant considering the safety factors. 3) Issue relevant policies and strictly control the emission of sulfur trioxide.