Nitrogen (N) is one of the most important and complex nutrients for the crop plants especially for grain yield and quality. Field trials were carried out in 2007-08 and 2008-09 growing years to investigate response of six oat cultivars (Seydisehir, Apak, Yesilkoy-330, Amasya, Checota and Yesilkoy-1779) to three N rates (0, 10 and 20 kg da-1) for agronomical traits. In the research the traits such as panicle number per m-2 (PN m-2), plant height (PH), grain number per panicle (GNP), grain weight per panicle (GWP), 1000-grain weight (1000-GW), grain yield (GY), biomass (BY) and harvest index (HI) were investigated. Results indicate that agronomical traits significantly differed for the years, cultivars and N rates, except PH for cultivars. Among the cultivars, Checota had the highest GWP, 1000-GW and GY (3.12 g, 38.5 g and 259.6 kg da-1 respectively), while Seydisehir had the highest PN m-2 and BY (543 PN m-2 and 1666 kg da-1 respectively). Investigated traits were gradually increased with increasing of nitrogen rates. Checota cultivar had the highest GY, while Seydisehir cv. had the highest BY at 20 kg da-1 N rate