[Objective] This study aimed to investigate the effects of meteorological factors and crop planting area changes on maize water requirements in the Ningxia Yellow River irrigation area. [Methods] The PenmanMonteith equation and single crop coefficient method were employed to calculate maize water requirements and analyze their spatiotemporal variations in the Ningxia Yellow River irrigation area. The rescaled range analysis（R/S） method was used to predict future trends in maize water requirements. Partial derivative-based sensitivity analysis and logarithmic mean divisia index（LMDI） decomposition were utilized to examine the impacts of meteorological factors and planting area changes on maize water requirements and to identify the primary influencing factors. [Results] Maize water requirements exhibited distinct spatial heterogeneity, increasing from the central to the northern and southern ends of the irrigation area, with overall lower values in southwest than in northeast. Future water demand predictions indicated an increasing trend for maize water requirements at the Huinong and Yinchuan stations. Among meteorological factors, relative humidity showed the highest sensitivity coefficient. Unit-area maize water requirements increased with rising maximum temperature, minimum temperature, wind speed, and sunshine hours, but decreased with increasing relative humidity. Throughout the study period, changes in crop planting area were the primary factor driving variations in total maize water requirements. [Conclusion] The expansion of maize planting scale has a significant impact on the increase of total water requirements, while meteorological factors play a relatively minor role in the variation of total water demand during this period. The research findings can provide decision-making support for determining rational crop planting structures and scales, as well as adaptive water resource management in irrigation areas under climate change scenarios.