The processes of outbursts of a landslide dam, consisting of sand, and a mixture of sand and bentonite were observed through flume experiments. The discharge rate of the outflow overflowing the top of the dam was measured. As a result, it was observed that there were a number of peaks appearing in the flow discharge hydrograph during the outbursts. The maximum discharge rate was observed at its first peak when the vertical erosion rate was most intensive. The value was then in a range from a few to a few tens times the inflow rate. These peak flow discharge rates were evaluated through the equation of Tabata et al. The second and the following peaks were caused by horizontal erosion in the eroded channel. Further, we also found that the temporal variations of the outbursts on the landslide dam were affected greatly by the adhesive qualities of the landslide dam earth.
