Watershed analysis based on morphometric parameters gives an idea about the basin characteristics regarding slope, topography, soil condition, runoff characteristics, surface water potential, etc. These characteristics are very important for watershed planning and management. The potential disaster of flash flood and soil erosion is anticipated by studying morphometric parameters of the Kaligandaki basin. In the middle Kaligandaki sub-basin, the Kaligandaki river from Tatopani to Modibeni has human settlements concentrated along its sides like the Beni bazaar. They are always at risk of erosion and flood inundation. In monsoon, due to heavy rainfall, the Kaligandaki river erodes and inundates the lands near its bank. From the analysis of morphometric parameters, the erosion and inundation of land near river banks are justified. The study of flood inundation map obtained by processing discharge of river in HEC-RAS indicates the settlement and structures near the river are very prone to flood disaster. This study can be referenced for flood planning and disaster reduction measures in the Beni bazaar.