Abstract: The heterosis of main agronomic and yield characters of F1 and F2 generations respectively from six cross combinations was analyzed. As far as the average heterosis of different cross combinations was concerned, both F1 and F2 genarations expressed negative over male-parent heterosis in plant height and technical length traits, however, positive over male-parent heterosis existed obviously in yield traits, including fruits per plant、seeds per fruit、1000-seed weight and seeds yield per plant. Compared with F1 generations , the average heterosis of F2 generations was lower.The order of heterosis is seed yield per plant＞fruits per plant＞1000-seed weight＞seeds per fruit. The heterosis expression of F1 and F2 generations from different cross combinations was different. The heterosis of 1S ×Heiya No.15 in yield traits was the largest among the six cross combinations not only in F1 genarations but also in F2 genarations.