Falling groundwater table depth (WTD) and excessive nitrogen (N) fertilization have caused both crop yield reductions and environmental contamination. However, the combined effects of WTD and N application rate on maize production and resource use efficiency remain unclear. In this study, an automated groundwater level control system was used to investigate the impacts of WTDs (2 m and 4 m) and N rates (210 and 280 kg ha-1) on soil properties, yield components, crop evapotranspiration (ETc), crop water productivity (WPc), and partial factor productivity of N (PFPN) across two maize growing seasons (2023-2024). Results showed that increased N rate at WTD of 2 m caused soil nutrient loss, while at a WTD of 4 m, it improved soil organic carbon, nitrogen, phosphorus, and potassium. Maize yields decreased with deeper WTD and lower N rate, with WTD contributing more to yield variation than N rate (16 % vs. 10 %). Grain number had a stronger effect on yield than kernel weight (0.65 vs. 0.40), with the former mainly influenced by WTD and the latter by N rate. Deeper WTD reduced ETc by 68 mm, groundwater evaporation by 73 mm, and the contribution of groundwater to ETc by 11 %. WPc did not differ significantly among treatments, suggesting a linear yield-ETc relationship. Both lower WTD and N rate increased PFPN, with WTD affecting N utilization efficiency and N rate influencing N uptake efficiency. This study offers practical insights into water-fertilizer managements under fluctuating groundwater conditions to support sustainable maize production.