This　study　developed　a　discrete　element　simulation　model　based　on　the　2D　particle　flow　code　(PFC2D),　of　which　the　mesoscopic　parameters　were　calibrated　by　the　indoor　experiments,　to　investigate　the　rainfall　erosion　damage　of　residual　soil　slope　in　the　intermittently　frozen　area.　It　is　to　be　noted　that　the　runoff　scouring　action　was　simulated　according　to　the　equivalent　rainfall　method,　the　soil　particles　on　the　slope　were　given　initial　velocity,　and　the　water　absorption　was　considered　by　increasing　the　unit　weight.　The　results　indicated　that　the　scouring　action　only　caused　superficial　erosion　with　the　main　damage　region　at　the　foot,　regardless　of　the　FT　effect.　A　splitting　phenomenon　was　observed　in　the　lower　part　of　the　steeper　slope　under　the　FT　effect.　Moreover,　regardless　of　the　FT　effect,　the　gentler　slope　tended　to　incur　spalling　rather　than　a　splitting　phenomenon,　where　the　soil　particles　slid　along　the　structural　plane　with　strong　anti-scouring　ability.　Besides,　the　gentler　slope　maintained　higher　stability　and　shorter　scouring　time.　Finally,　the　scouring　velocity　increased　the　erosion　damage　to　a　large　extent.