In　order　to　carry　out　stability　analysis　of　soil-rock-mixture(SRM)　slopes,　an　improved　numerical　manifold　method　(NMM)　with　multiple　layers　of　mathematical　cover　systems　is　proposed.　For　SRM　problems,　the　computational　cost　of　the　improved　NMM　is　smaller　than　that　of　the　traditional　NMM.　Besides,　an　improved　shear　strength　reduction　technique(ISSRT)　which　can　eliminate　spurious　plastic　deformation　of　the　slopes　is　implemented.　Based　on　the　improved　NMM　with　multiple　layers　of　mathematical　cover　systems,　the　stability　of　three　slopes,　namely,　a　homogeneous　slope　and　two　SRM　slopes　with　different　contents　of　rock　blocks　is　analyzed.　The　numerical　results　about　the　three　slopes　indicate　that:　1)　the　proposed　numerical　model　can　obtain　the　FOS　of　a　slope　with　high　accuracy;　2)　the　bigger　the　content　of　rock　blocks,　the　larger　the　FOS　of　the　SRM　slope　will　be;　3)　due　to　the　existence　of　rock　blocks,　the　failure　mode　of　a　SRM　slope　is　different　from　that　of　a　homogeneous　soil　slope.