Analyzed　the　high　stress　distribution　characteristics　of　the　deep　tunnels　and　studied　the　mechanism　of　the　blasting　by　numerical　calculation　and　model　test.　The　results　show　that　the　stress　field　distribution　of　blasting　is　not　symmetrical　because　the　level　stress　is　bigger　than　the　vertical　stress　in　deep　rock　tunneling.　Cracks　of　blasting　extend　in　the　direction　of　less　stress　first.　Clamping　effect　boosts　up　around　the　boreholes　and　the　intensity　of　rock　increase.　Put　forward　the　principle　of　blasting　parameters　design　and　improved　the　quality　of　rock　blasting　about　the　deep　rock　excavation.