Abstract: To improve the efficiency and scientificity of the site selection for hydrological rainfall radar, this study proposed a quantitative siting methodology based on Analytic Hierarchy Process (AHP). Utilizing a dual-phase decision-making framework of "rigidity and elasticity", the methodology calculated the weights of eight key factors influencing radar siting and established a comprehensive evaluation index system. Based on the constructed site selection evaluation system, we conducted a systematic quantitative analysis and optimal site selection, and provided an example for the site selection of the Wanjiazhai Water Conservancy Hub rainfall radar for practical verification. The findings reveal that sight conditions, geological stability, electromagnetic environment, and land use suitability constitute the four core disqualifying factors. The AHP quantitative model can avoid site selection bias and provide references for the hydrological rain-measuring radar networks construction.