The Normalized Difference Vegetation Index (NDVI) can be an indicator for plant growth response and ultimately yield to water and nitrogen (N) requirements in semi-arid region. To assess the growth and development of maize through NDVI measurements under various N and irrigation water regimes, a field trial was conducted over two consecutive years at the University of Agriculture, Faisalabad, employing a split-plot arrangement. The study involved three irrigation water regimes (IWR): normal irrigation, water deficit at the vegetative growth stage, and water deficit at the reproductive growth stage. Additionally, five N application rates (NR) were applied: 100, 150, 200, 250, and 300 kg ha-1 during each study year. The canopy reflectance NDVI data was measured using a Handheld GreenSeeker at ten-day intervals. The results showed that deficit irrigation regimes reduced NDVI, with the maximum decrease observed in IWR3 during both growing seasons. The results also revealed that an increase in N fertilizer application rates led to higher values for NDVI, leaf area index (LAI), and total dry matter (TDM). A highly significant and positive correlation of LAI and TDM, was observed with NDVI under different irrigation regimes (ranging R2 = 0.67 to 0.97) and N application rates (ranging R2 = 0.58 to 0.97) throughout the entire growing season. Additionally, all other growth and yield parameters of maize showed a positive and significant correlation with the NDVI values. The study findings suggest that utilization of NDVI measured with a handheld GreenSeeker sensor can effectively determine the impact of irrigation and N on maize grown in a semi-arid region. Therefore, handheld GreenSeeker sensor has emerged as a promising tool as a more efficient and rapid alternative method for non-destructively measuring maize growth and potentially assessing yield.