[Objective] The spatiotemporal pattern evolution and driving factors of agricultural grey water footprint efficiency were explored in order to provide a scientific reference for promoting agricultural water conservation and comprehensive water pollution control, and high-quality agricultural development in the Yellow River Basin. [Methods] A grey water footprint model, the Theil index, and the log-average Dietscher index were used to estimate the efficiency of agricultural grey water footprint for nine provinces in the Yellow River basin from 2000 to 2021, and the spatial-temporal evolution pattern and driving factors were discussed. [Results] ① The agricultural grey water footprint efficiency during 2000—2021 in the Yellow River basin showed an overall upward trend over time, with an average annual efficiency of 0.235 8 yuan/m³. Inner Mongolia had the highest efficiency (0.467 0 yuan/m³), and Qinghai had the lowest efficiency (0.026 3 yuan/m³). ② The annual average contribution rate of the regional gap in agricultural grey water footprint efficiency was 80.11%, and the annual contribution rate of the upstream gap was 75%, which was the main reason for the large gap in agricultural grey water footprint efficiency in the Yellow River basin. ③ The total effect of agricultural grey water footprint efficiency was 0.202 4 yuan/m³, and the cultivated land resource effect and agricultural environment effect were the main factors in promoting and inhibiting the agricultural grey water footprint efficiency, with contribution values of 0.442 7 yuan/m³ and -0.4406 yuan/m³, respectively. ④ The driving effect of agricultural grey water footprint efficiency in the Yellow River basin can be divided into four models. Different models have different ways of improving agricultural grey water footprint efficiency in different regions. [Conclusion] The nine provinces in the Yellow River basin should adopt different development strategies according to local conditions, optimize the agricultural structure, reduce the intensive use of fertilizers and pesticides, strengthen agricultural water management, and improve agricultural grey water footprint efficiency.