The　Tangjiashan　landslide　dam　failed　on　June　10,　2008,　which　was　the　largest　one　formed　during　the　Wenchuan　earthquake　in　China.　No　human　lives　were　lost　in　this　dam　failure.　This　paper　presents　a　description　of　the　dam,　including　the　dam　geometry,　the　hydrograph　and　the　reservoir　capacity,　the　diversion　channel　and　the　drainage　from　the　lake.　Several　empirical　models　are　applied　to　predict　the　breach　parameters,　the　peak　outflows　and　the　reservoir　volumes　during　this　breach　event.　The　main　objective　of　the　study　is　to　compare　various　prediction　models　and　to　make　recommendation　of　the　best　model　for　the　prediction　of　the　breach　width,　the　failure　time,　and　the　peak　outflow.　The　breach　widths　predicted　by　the　Froehlich　methods　with　considerations　of　the　reservoir　storages　and　the　effect　of　failure　mode　are　considered　to　be　more　reasonable.　All　prediction　methods　discussed　in　this　paper　are　found　to　underestimate　the　breach　formation　time　due　to　the　complex　material　and　the　large　thickness　of　the　dam.　The　results　from　the　soil　conservation　services　(SCS)　method　compare　well　with　the　observed　peak　outflow.　The　Marone　method　in　combination　with　the　coefficient　expressions　proposed　by　Macchione　gives　excellent　results　in　the　simulation　of　the　reservoir　volume-level　curve.