This paper summarizes the assessment of debris flows in the town of Matucana, Peru located in Western Andes, approximately 75 km east of Lima. It also describes the application of the FLO-2D model to simulate debris flows and to generate a hazard map for the area. Large debris flows affected Matucana in 1959 and 1983. In this region large debris-flow events are conditioned by regional rainfalls and are a greatest threat during E1 Niño years and the year following E1 Ninõ. The FLO-2D model was implemented and first calibrated using data from the previous debris flow events. Then the model was used to simulate events for different return periods. The resulting depth and velocities for each return period were used to generate a hazard map. This study is part of the Multinational Andean Project: Geoscience for Andean Communities begun in 2002, and is jointly funded by the Canadian International Development Agency, the Geological Survey of Canada and the National and Geoscience Agencies of Argentina, Bolivia, Chile, Colombia, Ecuador, Peru and Venezuela. The resulting hazard map will be used by local authorities to design structural and nonstructural mitigation measures. © 2007 Millpress.