Abstract: The EST isozyme zymograms of two corn inbreds were studied using the PAGE technique. The results show that when essterase isoenzyme analysis was done using a single grain of seed the enzyme spectrum was distinct, repetition was good .The zymograms of 1 and 4 or 2 and 3 were similar, suggesting that they may be the same sample. 1 appeared closely related to 2 genetically , they may be different types that it have the certain pedigree relationships. Based on a comparison of the botanical characteristics of the two species, a discussion is made of their application of corn Hybrids and it can be concluded that it is practical to use esterase isoenzyme for identifying the truth and pedigree relationship of corn inbreds. The method has the merits of fastness and accuracy.