When　a　retaining　wall　is　built　near　a　building　or　a　mountain,　the　backfill　width　is　often　limited.　It　limits　the　use　of　the　classical　theoretical　formula　based　on　the　assumption　of　an　infinitely　large　half-space.　Finite-element　analysis　shows　that　when　the　retaining　wall　movement　is　translational,　one　to　three　slip　surfaces　will　develop　from　the　wall　heel,　and　eventually　develop　to　the　surface　along　the　soil-wall　or　soil-rock　interface.　An　effective　model　for　calculating　the　active　earth　pressure　of　narrow　granular　backfill　against　the　wall　under　translational　mode　is　established　by　taking　into　account　the　inclination　angle　of　the　rock　face　and　the　friction　angles　of　the　soil-wall　and　soil-rock　interfaces.　The　active　earth　pressure　under　the　failure　mechanisms　of　one　to　three　slip　surfaces　are　given　by　using　the　limit　equilibrium　method　and　the　whole　analysis　method　of　sliding　wedge.　The　coefficient　of　active　earth　pressures　is　as　low　as　0.5-0.7　times　the　Coulomb　solution　and　the　location　(h0/H)　of　the　resultant　of　active　earth　pressures　ranges　from　0.34　to　0.44.　The　influence　of　different　parameters　on　the　number　of　slip　surfaces　was　also　studied　by　parametric　analysis.　©　2019　American　Society　of　Civil　Engineers.