In order to define the dynamic difference of kernel moisture content and dehydration rate in the different parts of maize ear, this study used eight cultivars with different growth stages and dehydration rates in Yinchuan, Ningxia (spring maize region) and Xinxiang, Henan (summer maize region). We divided the maize ear into five parts vertically, then measured the kernel moisture content and calculated the kernel dehydration rate in different parts periodically. The results showed that during the middle and late stage, the kernel moisture content in the upper part of ear was lower than that in the middle and lower parts. The differences of kernel moisture content in various parts of ear was lower before physiological maturity than that after physiological maturity. The range of different parts of the kernel moisture content was less than 3% in test maize cultivars on 20 d before physiology maturity. The range at maturity was 0.6%-5.2%, and the maximum range was 6.2% after physiological maturity. The dehydration rate gradually decreased from the top to the bottom of ear, and there were differences in different cultivars. The kernel dehydration rate in different parts of ear was great in Xianyu 335, Dika 517 and Dika 519. The range of kernel moisture content in different parts were negatively correlated with dehydration rate of middle kernels and total ear.