The main objective of this study was to adjust the corn population and nitrogen fertilization according to management zones, based on past grain yield maps (seven of soybean and three of corn) and soil electrical conductivity. The study was carried out in Não-Me-Toque, Rio Grande do Sul, Brazil, and it was conducted in a factorial strip blocks with 3 repetitions in each management zone, being the treatments: corn populations (56000, 64000, 72000, 80000 and 88000 plants ha^-1), nitrogen rates (0, 60, 120, 180 and 240 kg ha^-1) and management zones (high, medium and low potential). There was a significant interaction between management zones and corn population and also between management zones and nitrogen rates, for grain yield. Optimization of the corn plant population and nitrogen rate within the field increased grain yield compared to the reference plant population (72000 plants ha^-1) used by the farmer, and nitrogen flat rate. In the low potential zone, the highest yield was reached with the lowest tested population (56000 plants ha^-1) and 164 kg ha^-1 of nitrogen, while in the high potential zone the corn population, which provided the best profitability, was 88000 plants ha^-1, with 195 kg ha^-1 of nitrogen, so that, this zone was the most responsive to nitrogen and corn population. In the medium potential zone, the reference corn population was the most profitable, with 175 kg ha^-1 of nitrogen.