Kernel related traits are important determinant factors for maize yield. In order to explore the genetic basis of kernel variation about important Chinese maize germplasm, kernel related traits were investigated in a panel of 627 diverse important maize inbred lines by means of correlation analysis and regression analysis. It was indicated that HKV and HKW were significantly correlated and HKV could explain 78% phenotypic variation explained (PVE) of HKW. Regression analysis among different heterotic groups indicated that kernel width (KW) contributed the most to HKV in the heterotic groups of Reid, LRC, Lancaster and P with the PVE varied from 54% to 71%. While in TSPT, kernel thickness (KT) and kernel length (KL) made great contribution to HKV with the PVE of 45% and 22%, respectively. This result would provide positive information for kernel trait improvement in maize breeding.