So　far,　there　are　still　many　unsolved　problems　in　seismic　analysis　and　failure　mechanism　study　of　underground　structures　in　China.　On　the　basis　of　analyzing　and　summarizing　the　existing　theoretical　analysis　and　experimental　study　of　seismic　response　of　underground　structures,　six　key　issues　need　to　be　seriously　considered　and　further　studied　in　the　near　future.　They　are　model　techniques　of　shaking　tests　for　underground　structures,　nonlinear　dynamic　constitutive　model　of　soil,　seismic　failure　mechanism　of　bearing　members　of　underground　structures　under　high　axial　loads,　asynchronous　seismic　wave　motion　input　and　seismic　response　of　underground　structures　under　it,　physical　fundamentals　and　constitutive　model　of　large　post-liquefaction　deformation　of　saturated　sand,　and　finally　large-scale　three-dimensional　nonlinear　dynamic　soil-structure　interaction　model.　Study　on　the　issues　above　will　give　some　help　to　consummate　theoretical　seismic　analysis　methods　and　model　test　techniques　of　underground　structures,　and　to　get　seismic　response　characteristics　and　failure　mechanism　of　large-scale　underground　structures,　which　have　vital　scientific　meanings　and　great　value　in　engineering　practice.