Dynamic　interactive　geophysical　finite　element　model　for　underground　structures　was　developed　to　precisely　analyze　underground　structures　subjected　to　blast　shocks.　The　dynamic　parameters　for　the　vibration　environment　are　described　in　the　method.　The　finite　element　model　includes　wave　reflections,　diffraction,　and　transmission　when　the　shock　wave　encounters　the　structure.　The　analytical　results　show　that　the　200%　error　in　classical　methods　is　reduced　to　20%　with　this　method.　The　method　can　be　used　to　analyze　isolation　problems　of　underground　structures　subjected　to　blast　loads.