Efficient water management is critical in modern agriculture, particularly in the face of increasing water scarcity and climate variability. Maize, a major cereal crop worldwide, is highly sensitive to water availability, making irrigation management a key factor in sustaining both yield and grain quality. This study was conducted to investigate the impact of deficit irrigation, including partial root-zone drying (PRD) techniques, on the grain quality parameters of maize. The experiment evaluated the effects of different irrigation levels 100% (full irrigation), 75%, 50% (with and without PRD), and 25% on key biochemical attributes of maize grain. Results revealed a significant influence of irrigation level on most grain quality parameters. ADF content increased progressively with reduced water application, peaking at 3.90% under 25% irrigation, while the lowest value (3.43%) was recorded under full irrigation. Conversely, NDF and hemicellulose contents were highest under full irrigation (19.13% and 15.70%, respectively) and decreased under severe water stress. Starch content also declined with increasing water deficit, with the maximum value under full irrigation and the lowest (63.33%) under 25% irrigation. Protein content was highest in the fully irrigated treatment, though differences among treatments were not statistically significant. Oil content showed a similar trend, with maximum values ...