Abstract: In order to breed new oat varieties with high yield, high quality, which are suitable for planting in the three provinces of Northeast China and Inner Mongolia, in the experiment, the maternal Bianfeng and the paternal Mullus were used for interspecific hybridization in 2015, and the breeding was carried out by the system derived method, then the variety comparison test, regional test and production test were carried out for the new oat varieties. The results showed that oat Longyan No.1 was obtained by breeding, the average hay yield and seed yield of this variety in 2019—2020 were 15 100.0 kg/hm~2 and 4 760.3 kg/hm~2, respectively, which increased by 16.84%, 11.71% and 14.96%, 11.11% compared with the control varieties of Mullus and Baiyan No.7, respectively. The difference was significant（P＜0.05）. The average hay yield of Longyan No.1 in these two years（2022,2023） and multiple locations（including Qiqihar City, Harbin City, Shuangyashan City, Suihua City） was 9 857.14 kg/hm~2, which was 18.11% higher than that of Qinghai 444（P＜0.01） and 45.29% higher than that of Qingyin No.2（P＜0.01）. The hay yield in the four test areas of Harbin City, Lanxi County, Dumeng County, Zhaodong City reached 11 812.73 kg/hm~2, 9 602.57 kg/hm~2, 12 263.64 kg/hm~2 and 11 961.97 kg/hm~2, respectively. Compared with the control variety of Baiyan No.7, the yield increased by 11.57%, 11.92%, 12.60% and 11.24%, respectively. The results indicated that the new oat variety Longyan No.1 had better production performance than its parent and could be planted in the three provinces of Northeast China.