Based on the measured rainfall data in adjacent areas

this paper analyzes the distribution law of regional rainstorm

and uses statistical analysis method and contour map method to compare and analyze the design rainstorm. Through collection and utilization of reservoir operation data

the rain ⁃ storm time history distribution and runoff generation and concentration parameters are analyzed and se ⁃ lected in combination with domestic design experience. The SCS method and IWHA rational method are used to calculate the design flood of dam site

and the flood regulation calculation is carried out. Accord ⁃ ing to calculation

the layout of Kirirom Ⅲ hydropower station can meet the flood control requirements. The research method fully utilizes the measured data

providing reference for flood control design of small and medium-sized hydropower projects in overseas regions with scarce data

especially in South ⁃ east Asia.