Flood is among phenomenon which bring about considerable damage each year. This has been attracted greatly by hydrologists. The factors such as physiography, geomorphology and human factors can accelerate this phenomenon in basins. For using water source, flood management, damming, watershed management and the most basic hydrologic studies, peak discharge is important, so accuracy of studies and the safeties’ level of the hydraulic structures and establishments are independent to it.In this research potential flood Zilaki and Firehrud drainage basins were studied by using of SCS method and finally were compared together. So Basin Hydrograph dimensions calculated by using of 24 hour rainfall, time of concentration, Curve Number, rainfall excess, time to peak and peak discharge.Then was design Hydrograph for basins in 2, 5, 10, 25, 50, 100 period time Results show, because of physiography of Firehrud basin, It has more ability for making flood than Zilaki basin.