Malpasset dam-break occurred in the south of France in 1959 and caused 421 casualties. This unique example of total failure of an arch dam makes it a case of utmost interest for testing and validating software. In the past, a scale model and a one-dimensional computation have been used to reproduce the accident. This paper presents two-dimensional computations of Malpasset dam-break performed with TELEMAC-2D. They provide an improvement on one-dimensional computations when there are:sharp bends in the river and when the flood Spreads in the coastal area. The study concludes that 2D simulations of flood-waves are already possible on domains with a length of some 10's of kilometres.