In　the　present　paper,　the　digital　image　processing　(DIP)　technology　is　employed　to　establish　the　structure　model　of　a　real　SRM　(soil-rock-mixture)　slope.　Based　on　the　structure　model,　the　most　recently　developed　strength　reduction　numerical　manifold　method　(SRNMM)　is　adopted　to　investigate　the　stability　of　the　SRM　slope.　Based　on　the　proposed　numerical　model,　the　testing　results　show　that:　1)　the　DIP　technology　can　accurately　build　the　structure　model　of　the　SRM　slope;　2)　the　SRNMM　can　obtain　the　slopes?　FOSs　(factors　of　safety)　with　satisfactory　accuracy,　as　well　as　obtain　the　main　failure　mode　of　the　slopes;　3)　the　presence　of　rock　blocks　will　improve　the　stability　of　the　soil　slopes.