Abstract:The purpose of this study was to analyze the variation tendency of panicle traits and Cheng's index and their relationship under different ecological environments. The F2 population from a cross between Indica variety Wanlun422 and Japonica variety Shengnong265 was used as materials, which was grown in Liaoning, Sichuan and Shanghai in the same year. The results showed that the panicle traits changed significantly in the three places, with the panicle length (PL) longer, the higher secondary branches (SB), but the lower seed setting rate (SSR), and SSR had extremely positive correlation with grain density (GD) in Sichuan and Shanghai. While in Liaoning, the shorter PL, the more primary branches (PB) and the higher SSR, but SSR had no extremely correlation with GD. The frequency distribution of Cheng's index, pubescences of leaf, panicle node length, color of spike and grain length/width under different environments were all japonicalinous, which were increasing from northern to southern of China. The Cheng's index with the panicle curve degree (PCD) had no significant correlation in the three places. In Sichuan the Cheng's index had extremely negative correlation with GD, but it had extremely positive correlation with SSR and 1000-grain weight (TGW). In Shanghai the Cheng's index had extremely positive correlation with SSR. In Liaoning the Cheng's index had extremely negative correlation with GD, PB, SB, Grains, but it had extremely positive correlation with PL. There is no denying the fact that coordinating the improvement of panicle structure and complementation between advantages and disadvantages through subspecies hybrid should accord to local conditions in the super high-yielding rice breeding.