The aim of the work was to analyze, using the CERES-Barley simulation model, the effect of different management strategies on the performance of old and modern malting barley cultivars growing in different sites of Argentina. The study was carried out considering weather database of 24 years for three sites. The management strategies considered were the combination of different N availabilities at sowing (from 20 to 180 kgN ha-1) and different water scenarios (low, mean and high rains during the fallow period or along the crop cycle). As a consequence of the combination of the different cultivars, sites, and N and water scenarios, grain yield ranged from 0.5 to 6.0 Mg ha-1, with a general mean of 3.0 Mg ha-1. The increase in grain yield by the use of the modern cultivar was in mean of ca. 1.2 Mg ha-1. With low N availabilities at sowing (< 40 kgN ha-1) the performances of the old cultivar was 30% of the attainable yield with the modern cultivar; while with increases in the N availability (> 140 kgN ha-1) the differences between cultivars were of ca. 80%. On the other hand, by effect of the available water in the fallow period the average profit in grain yield by the use of the modern genotype was of 0.4 kg ha-1. The old cultivar (31 kggrain/kgN) presented lower nitrogen use efficiency (NUE) than the modern cultivar (39 kggrain/kgN). However, for each site, changes in NUE were, in relative terms, similar between both genotypes. In conclusion, the impact of variations in the water or N availabilities on grain yield were smaller in the old cultivar that in the modern one and, independently of the site, the modern cultivar exhibit higher yield than the old cultivar at any management scenario.