Abstract: Esterase isozyme zymograms of endosperms at milk stage were analyzed by polyacrylamide vertical slab gel electrophoresis. It was shown that Aegilops squarrosa, Ae. ventricosa and Ae. crassa with D genomes all had E1-1 band with the same migration rate. In zymograms, the two bands E1-1, E1-2 of common wheat (AABBDD) and emmer wheat (AABB) were actually each compossed of two closely adjacent bands. Zone E3 of the two species had five bands each. There were no difference in migration rate of these bands between the two species, but the activities of these enzymes were different and they showed regular change. Zymograms of the hybrids of reciprocal crosses between emmer and common wheat are mainly tended to maternal types and it is representing the dosage effect of D genome.