Abstract:Bt gene (GFM CrylA) was induced into immature embryos derived from Tie7922, a Chinese northeast spring maize inbred line, by particle bombardment. Transgenic lines with stable resistance to corn-borer were gained by the inoculation of corn-borer eggs in field and the experiment for leaves fed on corn-borer indoor for three succession years. Three hybrids (Simi25Bt, Tongdan24Bt, Jidan209Bt) were created by the hybridization of transgenic lines and common lines, which belonged to improved Simi25, Tongdan24, Jidan209. The results of resistance identification showed that the difference of resistance among transgenic lines was very significant; it had the difference among individuals of the same line and among three hybrids, too. The resistance of hybrids derived from transgenic lines was more than that of common hybrids (CK). The investigation of agronomic characters showed that it had no significant difference between improved hybrids and CK in plant height, ear length, row number per ear, kernel number per row and 100-kernels weight. The paper thought that GFM CrylA (Bt) gene could be applied in the improvement of resistance to corn–borer and maize inbred lines with Bt gene could directly be applied in conventional breeding.