A　cantilever　retaining　wall　incorporating　a　long　relief　shelf　is　a　specific　form　of　retaining　wall.　However,　currently,　there　are　no　reports　investigating　this　retaining　wall　rotating　about　the　bottom.　Herein,　the　failure　mode　of　semi-infinite　noncohesive　soils　is　studied　using　the　finite-element　limit　analysis　method　(FELA)　when　the　wall　rotates　about　the　bottom.　The　results　show　that　the　backfilled　soil　initiates　the　development　of　first　and　second　failure　surfaces　at　the　end　of　the　wall　heel,　and　the　third　failure　surface　propagates　at　the　shelf＇s　end.　In　the　failing　soil,　there　are　numerous　subfailure　surfaces　parallel　to　the　first,　second,　and　third　failure　surfaces.　By　considering　both　the　effect　of　the　relief　shelf　and　the　equilibrium　limit　analysis　of　the　differential　soil　slice,　this　study　derived　a　formula　for　calculating　the　active　earth　pressure　of　cantilever　retaining　walls　with　the　long　relief　shelf.　The　effect　of　three　different　parameters,　i.e.,　relief　shelf　length　and　location,　and　wall　heel　length,　on　the　distribution　of　active　earth　pressure,　the　total　active　earth　pressure,　and　its　application　point　was　studied.　The　longer　the　relief　shelf　and　the　shorter　the　wall　heel,　the　lesser　the　active　earth　pressure.　Consequently,　when　the　relief　shelf　is　set　at　the　height　of　0.3　times　the　wall　height　from　the　top　of　the　wall,　the　active　earth　pressure　is　the　smallest.