Floods are one of the most common and devastating natural disasters, causing severe damage to the environment, the infrastructure, and the socio-economy as well. Performing a flood hazard assessment to recognize the flood-prone areas is very helpful for decision makers to manage and mitigate the flood risk. This article studies the flood hazard assessment in Northwest Vietnam by integrating the Geographic Information System (GIS) and Multi-Criteria Decision Analysis (MCDA). The flood hazard indicators have been analyzed. Weights of criterion, namely Elevation, Slope, Land Use/Land Cover, and Rainfall, were estimated using the analytical hierarchy process (AHP) technique. The flood hazard map was generated using ArcGIS-based weighted overlay modeling.