With the permission of surrounding rock conditions,adopting the full-face smooth blasting technology can accelerate construction progress and improve construction efficiency in large section tunnel blasting excavation.Meanwhile,the rationality of blasting technical parameters will directly determine the blasting effect of full section excavation.According to the engineering geological conditions and drilling machinery characteristics of Huangbaishan long and large tunnel of Jiangxi-Shenzhen high-speed railway,a full-face smooth blasting technology scheme of large-section tunnel is proposed.Furthermore,the drilling and blasting parameters of tunnel are determined according to the engineering analogy and the empirical formula calculation.Field blasting tests show that the contour of the tunnel excavation section is relatively smooth,the powder factor decreases from 1.16 kg/m3 to 1.07 kg/m3,the utilization rate of blastholes increases from 83.5% to 91.2%,and the peripheral hole mark rate increases from 73.6% to 87.4%,which efficiently improves tunnel excavation process and reduces construction costs.