通过逐步回归法分析影响灌溉水有效利用系数各因素的重要程度，筛选出节水灌溉面积为影响灌溉水有效利用系数的关键因素。考虑关键因素与时间序列两方面，基于逐步回归法、GM(1,1)模型和Logistic生长模型构建变权重组合模型。变权重组合模型的预测精度优于各单项模型，模拟效果与实际符合度高，适用于灌溉水有效利用系数的预测。最后采用变权重组合模型对广东省2023—2035年灌溉水有效利用系数进行预测分析。2023—2035年广东省灌溉水有效系数逐年提高，其中2035年预测值达到0.6792，高于全国绝大多数灌溉水有效利用系数的现状值。变权重组合模型预测法可为农业水资源规划与灌溉管理提供科学参考。

The irrigation water effective utilization coefficient serves as a crucial indicator to assess the efficacy of agricultural irrigation, as well as a vital component in implementing a stringent water resource management system. However, until now, there has been a lack of efficient and accurate methods for predicting the irrigation water effective utilization coefficient. In light of this, a novel prediction approach was presented for the irrigation water effective utilization coefficient.Initially, a stepwise regression analysis was employed to determine the significance of each factor contributing to the coefficient, with the water-saving irrigation area being identified as the primary factor influencing the irrigation water effective utilization coefficient. Secondly, the stepwise regression model was selected considering the key factors, and the GM(1,1) model and Logistic growth model were selected considering the time series. Finally, it was constructed of a variable weight combination model with enhanced prediction accuracy, which utilized the three weight values derived from the error values of the stepwise regression method, GM (1,1) model and Logistic growth model. The prediction error revealed that the curve of the variable weight model aligns well with the measure results curve, demonstrating a prediction accuracy that was markedly superior to that of the individual models, making it suitable for predicting the irrigation water effective utilization coefficient.The variable weight combination model was utilized to predict and analyze the irrigation water effective utilization coefficient in Guangdong Province from 2023 to 2035. The prediction result indicated that the forecast value of the irrigation water effective utilization coefficient will reach 0.679 2 in Guangdong Province by 2035.The theoretical reference is provided for the planning and management system of agricultural water resources. It is of great significance to the upgrading and modernization of irrigation districts in China as well as to the reform of agricultural water prices.