Abstract Defeng No.1 is a new middle-late mature Chinese cabbage F 1 hybrid bred from two self-incompatible lines Lubai 8SI and Xin No.1 DD. The growing period is 85 days. The leaf stalks are thin with little fiber. It is resistant to downy mildew, high resistant to virus. The yield is 82.71-83.11 t·hm -2, 2.7%-12.7% higher than that of contract variety Beijingxin No.3, with high quality and good commodities.