The basic principle of smooth blasting by protecting borehole wall with pipe is analyzed in brief.The smooth blasting technique with borehole wall protection was applied in tunneling in some phosphate mine.Comparing with traditional smooth blasting,this new smooth blasting technique can increase the length of peripheral hole remaining on rock surface by near 33%,reduce the unit volume consumption by about 0.233 kg/ m3,also can enhance tunneling rate.The practice showed that this new smooth blasting technique has good effect in reducing the failure of rock around roadway.