The increase in atmospheric temperature and alteration of the hydrological cycle are the main threats of climate change to wheat crop (Triticum aestivum L.). Furthermore, feeding a population which annually grows 1.1 %, promotes the expansion of agricultural frontier to soils with growth constraints. In this context, when in South America La Niña events occur, the cold phase of the ENSO climate phenomenon, in a greater area of the wheat crop region increases the risk of drought stress during grain filling. The aim was to study the response of five wheat cultivars to two irrigation treatments: Control and Stress. The experiment was conducted in a greenhouse using the bread spring wheat cultivars LE 2249, LE 2331, LE 2333, Baguette Premium 11 and Biointa 1001. Relative water content (RWC) was determined during the stress period, from anthesis to physiological maturity, and grain yield and its components at harvest. No significant interaction between cultivars and irrigation treatments were observed for yield per plant and RWC (P=0.3086 and P=0.0589, respectively), but it was significant for kernel weight and harvest index (P=0.0188 and P=0.0405, respectively). The cultivar LE 2333 was hardly affected by the Stress treatment, while Baguette Premium 11 and LE 2249 showed an intermediate response. In contrast, LE 2331 and Biointa 1001 were the most susceptible cultivars, decreasing their yield per plant 21.0 % (P=0.0206) and 21.2 % (P=0.0284), respectively. An early stress threshold in Biointa 1001 caused that kernel weight and RWC were not modified due to a decrease of kernels per plant. Whereas a late threshold in LE 2331 caused that both, kernel weight and RWC were affected. Cultivars with the latter type of response would be more suitable for regions with deep soils and/or with high probability of rain after anthesis.