The　depth　and　geometry　of　potential　failure　surface　is　the　fundamental　for　evaluating　the　mechanisms　of　a　landslide.　Traditional　techniques　to　acquire　information　on　potential　sliding　surface　are　mainly　drilling,　pitting,　and　trenching,　but　these　techniques　are　time　consuming　and　expensive.　In　this　study,　microtremor　signals　and　the　dispersion　curves　of　surface　wave　are　extracted　from　the　vertical　component　of　microtremor　records　using　the　spatial　autocorrelation　(SPAC)　method　to　estimate　shear　wave　velocity　structure.　The　results　suggest　that　the　buried　depth　of　phyllite　bedrock　is　approximately　47.4m,　and　the　thickness　of　weathered　bedrock　layer　is　about　9.9m　at　about　57.3m　deep,　which　could　be　interpreted　as　the　potential　sliding　surface　of　this　landslide,　in　accordance　with　borehole　data.　The　microtremor　survey　method　(MSM)　is　flexible,　non-invasive,　relatively　quick　and　deployable　on　the　landslide.　It　clearly　demonstrat　that　it　is　an　effective　tool　to　improve　the　drilling　success　rate,　and　hence　allow　a　large　scale　and　high　density　investigation　of　structure　characteristics　of　a　deep　seated　landslide.