Abstract: In order to provide theoretical basis to the increase of the yield and quality of oat in Inner Mongolia farming pastoral zone, the effects of nitrogen application amount on forage yield and feeding quality were analyzed. Three levels of nitrogen fertilizer amount (30, 90 and 150 kg/hm²) were conducted with two oat cultivars (‘Mengyan1’ and ‘8202’) under dry farming condition. The results showed that nitrogen application amount significantly affected the forage yield of the two oat cultivars. Compared with the low N treatment, the fresh yield and dry yield of ‘Mengyan1’ significantly increased by 8.42%-10.73% and 9.30%-13.38% respectively under high N treatment (P<0.05), which were also 17.58% and 19.28% higher than that of ‘8202’ under high N treatment. The content of crude protein and crude fat of the two oat cultivars increased with the increase of N application amount. The crude protein of ‘8202’ under high N application amount was 4.24%-14.14% higher than that of the other treatments, and was 29.85% higher than that of ‘Mengyan1’ under high N application amount. The crude fat of ‘8202’ under high N application amount was 0.44%-6.43% higher than that of the other treatments, and was 6.94% higher than that of ‘Mengyan1’ under high N application amount. The differences of the content of crude protein and crude fat between high and middle N application amount were not significant, but they were significantly higher than that under low N treatments (P<0.05). There were some differences between the two oat cultivars on forage yield and quality after N treatment. If the target was high forage yield, ‘Mengyan1’ should be the choice, its fresh forage yield and hay yield were 40891 and 7801 kg/hm² under high N treatment. If the target was high quality, ‘8202’ should be the choice, its crude protein and crude fat of the whole plant were 17.66% and 2.88%, which could reach 1080 and 166 kg/hm², respectively.