The purpose of this study was to evaluate the effects of various level of irrigation water application on corn root and shoot development at different plant growth stages. The study was conducted in 2010 at the Research Farm of Isfahan University of Technology. The study was conducted in 48 black pots with dimension of 800 mm height and 450 mm diameter. The field experiment included four level of irrigation water application, (1.00 SMD (soil moisture depletion) (T1), 0.85 SMD (T2), 0.70 SMD (T3), and 0.55 SMD (T4)), and four stages of plant growth (7-8 leaf, 12-13 leaf, tasseling, and milky grain stages). The experiments were arranged in a split plot in time in a randomized complete block with three replicates. The irrigation treatments were started at 30 DAP (days after planting). The time and amount of irrigation water application was determined based on MAD= 50% in full irrigation treatment (T1). The other irrigation treatments received a fraction of the amount of water that was applied for the T1 treatment, i.e., 0.85 for T2, 0.70 for T3, and 0.55 for T4 treatments. The leaf area (LA), above ground biomass (AB), plant height (PH), root length (RL), root dry weight (RDW), root area (RA) were measured four times at 38, 52, 73 and 87 DAP. A mixed model analysis of variance and least mean square analysis were used to determine the effect of irrigation treatment on corn shoot and root indices. Seasonal water application was 110.5 L for T1, 97.1 L for T2, 83.6 L for T3 and 70.2 L for T4 treatments. There was a significant effect of irrigation on root area (P 0.01) and ratio of root dry weight to above ground biomass (RDW/ABM) (P 0.01). There were also significant difference in RA and ratio of RDW/ABM among all irrigation levels. There was a significant effect of irrigation on root length (P 0.05). However, root length was not significant different among all irrigation treatment. There was a significant effect of irrigation on root dry weight (P 0.01). There were also significant different in RDW among all irrigation levels, except between T2 and T3 treatment. There was a significant effect of irrigation on plant height (P 0.01). However, plant height was not significant different among all irrigation treatment. There was a significant effect of irrigation on above ground biomass (P 0.01). Also, there was a significant effect of irrigation on leaf area (P 0.01). Leaf area was not significant different among T1, T2 and T3 treatment. There was a signification effect of irrigation on all measurement traits between full irrigation and sever deficit irrigation treatments. The minimum LA, ABM, PH, RL, RDW and RA were obtained at the T4 treatment. The ABM, LA and PH decreased respectively 40, 24 and 20% at the T4 treatment as compared to full irrigation treatment. The RDW, RL and RA decreased respectively 34, 20 and 30% at severe deficit irrigation treatment as compare to the T1 treatment. The maximum amount of RDW/ABM was accounted at severe deficit irrigation treatment. Keywords: Development of plant, Development of root, Maize, Water stress