Rankine　and　Coulomb　earth　pressure　theories　are　not　applicable　when　the　backfill　behind　the　retaining　wall　is　narrow.　This　paper　analytically　investigates　the　seismic　active　earth　pressure　of　an　inverted　T-type　retaining　wall　with　narrow　granular　backfill　under　translational　mode　using　a　pseudo-static　method　for　four　typical　seismic　active　failure　mechanisms　simulated　with　adaptive　finite　element　software.　Considering　the　failure　surface　reflections　on　soil-wall　and　soil-rock　interfaces,　four　corresponding　theoretical　solutions　using　the　limit　equilibrium　method,　Rankine　theory　and　the　horizontal　differential　layer　method　are　established　to　obtain　the　seismic　active　earth　pressure　of　the　backfill　and　the　inclination　angles　of　the　failure　surfaces.　The　derived　formulae　can　be　degenerated　into　either　the　static　or　the　semi-infinite　backfill　situations.　The　proposed　theoretical　solutions　are　verified　by　comparisons　with　the　finite　element　results　and　several　existing　theoretical　solutions.