Abstract: Exploring the efficiency and influencing factors of agricultural water conservancy investment in the Yellow River Basin is conducive to alleviating the misallocation of agricultural water resources in the basin and promoting the high-quality development of agriculture in the Yellow River Basin. The MinDS model is used to measure the investment efficiency of agricultural water conservancy in the Yellow River Basin from 2014 to 2020, and combined with the kernel density estimation to explore the dynamic evolution characteristics of the spatial and temporal distribution of its investment efficiency, and finally a panel Tobit model is established to analyze its influencing factors. The results show that:（1） The change trend of agricultural water investment efficiency in the whole country and the Yellow River Basin is basically the same, and the gap between the two is gradually narrowing. The regional differences in agricultural water conservancy investment efficiency in the Yellow River Basin are large. From 2014 to 2018, the pattern was downstream ＞ midstream ＞ upstream, and then it showed the characteristics of upstream ＞ midstream ＞ downstream.（2） The overall increase in the efficiency of agricultural water conservancy investment in the Yellow River Basin during the analysis period, the degree of dispersion in spatial distribution has increased, and the absolute difference between provinces has gradually expanded over time.（3） Before 2018, the low efficiency of agricultural water conservancy investment in the Yellow River Basin was due to its lower pure technical efficiency, and after 2018, it was due to its lower scale efficiency.（4） The level of economic development and the degree of fiscal decentralization are positively correlated with the investment efficiency of agricultural water conservancy, while the income level of rural residents and the illiteracy rate of rural residents are negatively correlated with it. In order to improve the efficiency of agricultural water conservancy investment in the Yellow River Basin, the allocation of agricultural water conservancy investment resources should be optimized, the management system of agricultural water conservancy investment projects should be improved, and an external environment conducive to the improvement of agricultural water conservancy investment efficiency in the Yellow River Basin should be created.