Abstract: The aims are to clarify the effects of characters on the yield per plant of interspecific hybrid between Brassica oleracea L. and Brassica rapa, and to promote the application of new interspecific hybrid in breeding. The agronomic characters of 133 BC1F4 individuals were analyzed with variation analysis, correlation analysis, path analysis and principal component analysis. The results showed that the number of invalid siliques had the maximum variation while plant height had the minimum variation. The yield per plant was positively correlated with plant height, the first branch height, the length of main inflorescence, the number of primary branches, the number of invalid siliques on main inflorescence, seed number per silique and the 1000-seeds weight, among which the yield per plant had significantly positive correlation with plant height. The main affecting factors of yield were: plant height, primary branch height, number of siliques on secondary branch and number of efficient siliques on main inflorescence. Moreover, the principal component analysis sorted the characters into 5 categories: the 1st and 3rd category controlled the yield and the other three were responsible for plant height, main inflorescence-controlling characters and branch-controlling characters, respectively. Thus, the yield per plant of interspecific hybrid between Brassica oleracea L. and Brassica rapa was mainly affected by plant height, the first primary branch height, the number of siliques of the secondary branch and the number of siliques on main inflorescence.