Landslides　often　occur　in　steep　mountain　areas　during　heavy　rainstorms.　Establishing　landslide　prediction　models　is　one　of　the　essential　strategies　for　disaster　prevention　in　mountain　areas.　The　kinematic　subsurface-flow　approximation　and　the　infinite-slope　instability　analysis　were　used　to　develop　a　rainfall-induced　shallow　landslide　prediction　model.　Firstly,　the　runoff　hydrograph　and　the　temporal　variation　of　soil　water　storage　were　obtained　by　calculating　the　runoff　yield　and　concentration　of　slope　according　to　the　theory　of　the　kinematic　subsurface-flow　approximation.　Then　the　temporal　variation　characteristics　of　saturated　water　level　was　studied.　Finally,　based　on　the　theory　of　the　infinite-slope　instability　analysis,　and　the　analyzed　slope　stability　the　temporal　variation　of　factor　of　safety　was　calculated.　The　Namasia　District　in　Kaohsiung　of　Taiwan　was　chosen　as　a　studied　area　to　test　the　applicability　of　the　model.　It　was　found　that　the　predicted　location　of　landslide　occurrence　during　Typhoon　Morakot　is　consistent　with　those　obtained　from　satellite　images,　and　the　values　of　the　calibrated　model　parameters　are　consistent　with　physical　meanings,　which　shows　that　the　physically　based　model　has　good　reliability.　Moreover,　the　variation　of　the　slope　factor　of　safety　was　analyzed　by　applying　double-peak　design　hyetographs　with　different　rainfall　peaks.　The　result　showed　that　when　the　rainfall　increases,　the　subsurface　flow,　and　the　saturated　water　level　raise　quickly　to　result　in　the　decreasing　of　factor　of　safety　value.　On　the　contrary,　while　the　rainfall　decreases,　the　rate　of　subsurface　outflow　is　higher　than　rainfall　intensity,　the　saturated　water　level　would　drop　slowly.　Hence,　the　slope　factor　of　safety　is　increasing　and　gradually　returns　to　its　natural　state.　Moreover,　the　influence　of　soil　thickness　on　slope　stability　was　further　studied　during　the　rainstorms.　The　results　showed　that　factor　of　safety　is　reduced　as　the　increasing　of　the　soil　thickness.　It　also　reveals　that　if　a　low-peak　rainfall　occurs　and　followed　by　a　high-peak　rainfall,　it　would　result　in　a　higher　possibility　of　landslides.　It　was　expected　that　this　study　can　give　a　clear　physical　explanation　for　the　landslide　occurrence　and　provide　a　useful　tool　for　landslide　prediction.　Copyright　©2021　Advanced　Engineering　Sciences.　All　rights　reserved.