Seven early indica rice varieteies cultivatied in Guangdong were selected as parents, making twelve pairs of reciprocal combinations, to determine the relative content of the pI (isoelectricpoint) range protein components of the highest nutrition based on the isoelectrofocusing-polyacrylamide gel electrophoresis (IEF-PAGE) separation and the quantity fixed according to the scan, in an attempt to find out the parent-descendant (F 1) relationship in the relative content by statistics. The result indicated that there was a significantly positive correlation between parents and their next generation which was more closely related to the female parent than to the male parent. The result with the study method has important significance in the nutrition quality breeding of rice proteins.