The　force-deformation　curve　of　a　reinforced　concrete　structure　in　push-over　analysis　is　used　to　compute　the　corresponding　damage　index.　A　simplified　and　practical　method　is　established　for　seismic　damage　assessment　in　combination　with　capacity　spectrum　method.　The　two-dimensional　capacity　spectrum　method　and　the　combination　of　the　damage　in　two　directions　are　discussed.　A　numerical　example　using　single　and　double　horizontal　capacity　method　and　time　history　analysis　demonstrate　that　the　response　and　damage　of　structure　can　be　computed　accurately　in　the　two-dimensional　capacity　method.　The　common　trend　of　structural　torsional　response　can　also　be　reflected.　The　results　show　the　two-dimensional　capacity　method　is　valid　and　simple.　©　(2011)　Trans　Tech　Publications.