In order to investigate the filling characteristic of the main promoted corn varieties under irrigation and drought condition in Huang-huai-hai area, 12 corn varieties were selected and cultivated in irrigated land and rainfed land. Study was made on dry matter accumulation quantity, filling rate and yield of these varieties. The results show that: Irrigation has the most obvious yield-increasing effect to the varieties of Jinsai29, Xundan20, Zhengdan958 and Zhongke No.4; but has reverse function to Xundan009 and Xundan18. Irrigation promotes at different degree the average filling rate and duration of all the varieties, among which Jinyu 8, Zhongke No.4 and Xundan18 have greater scope of promotion. Using cluster analysis, the treatments of irrigation and drought are divided into three types. In accordance with various adaptability of different varieties to irrigation and drought,we should arrange the varieties in their suitable regions, so as to optimize corn planting structure and raise the output.