The study is carried out with a purpose to apply various techniques and tools in ArcGIS 10.5 for the delineation of Mand catchment, thirteen sub-watersheds and developing methods in order to calculate the weighted curve number for the all the thirteen sub-watersheds of Mand catchment in ArcGIS 10.5. Multiple layers like Hydrologic soil group layer, DEM and Land Use Land Cover layer was combined and CN map was prepared. In particular, SCS-CN (Soil Conservation Curve Number) is a method through which the estimation of the direct runoff can be achieved with the curve numbers determined. This method comprises numerous important properties of the watershed such as Hydrological Soil Groups and land use/ land cover, antecedent moisture content (AMC) which will use as an input for various hydrological model.