【Objective】 The high grain dehydration rate and the low grain moisture content at harvest are two ear characters, which can be established for maize mechanical grain harvesting. Ear characters are decided by genes and have close relationship with grain dehydration. This internal relationship and the key ear characters that can characterize the traits of grain dehydration remain unknown, which are of great significance for breeding and screening of suitable varieties. 【Method】 The report researched on a total of 22 main cultivars of summer maize in HuangHuaiHai plain, and their ear characters were divided into 41 parameters covering bract, grain, cob and ear-pedicel. In 2015 and 2016, these parameters were measured and were used in correlation analysis with five grain parameters describing the dehydration rate, including the grain dehydration rate before physiological maturity (GDRbpm), the grain dehydration rate after physiological maturity (GDRapm), the total grain dehydration rate (GTDR), the grain moisture content at physiological maturity (GMCpm) and at harvest (GMCh). 【Result】 These 41 parameters were significantly different between the 22 cultivars, and there were some parameters significantly linked to grain dehydration. The bract length had a significantly negative relationship with GDRapm and a significantly positive relationship with GMCh. The value of “bract length/ear length” had a significantly negative correlation with GDRapm. The ear angle was positively correlated to GTDR at a significant level. The cob moisture content at physiological maturity had significantly positive relationships with GMCpm and GMCh. The grain number per ear was positively correlated to GDRbpm and GTDR at a significant level. The value of “ear length/grain number per row” had significantly positive relationships with GDRbpm, GDRapm and GTDR and had a significantly negative relationship with GMCh. The 100-grain dry weight at physiological maturity was negatively correlated to the grain moisture content at the significant level. There were no significant correlations between the other ear parameters and the five grain dehydration parameters.【Conclusion】 The current cultivars had different ear characters in HuangHuaiHai plain. These parameters contributed to grain dehydration rate, including the shorter bract, the lower moisture content of cob at physiological maturity, the larger ear angle, the fewer grain number per ear, and the smaller grain, which could be used in breeding and screening of mechanical grain harvest cultivars.