The timing of nitrogen application in oats can improve the efficiency of use of the nutrient and the expression of productivity and quality of grains. The objective of the study was to indicate the best time of application of nitrogen in oats, considering different conditions of nitrogen dose in the sowing/topdressing in the expression of productivity and the effects on the indicators of industrial and chemical quality of grains, considering the main succession systems of cereal cultivation in Brazil. The experiment was conducted in 2018, in Augusto Pestana, RS, Brazil. The design was randomized blocks with four repetitions, in a 3 × 4 factorial scheme, with three doses of nitrogen at sowing (0, 30 and 60 kg ha-1), changing the topdressing dose by the total supply of 70 and 100 kg ha-1 in succession system soybean/oats and corn/oats, respectively, with the timings of supply in topdressing at 0, 10, 30 and 60 days after emergence. The total doses were defined looking for grain yield expectations of 4000 kg ha-1. In the management of nitrogen in oats, the absence of the nutrient at sowing and application of the total dose in topdressing around 30 days after emergence provides advantageous results, improving productivity and indicators of industrial and chemical quality of grains.