Abstract: Isozymes of peroxidase of 10 species in Juglans L. were analyzed by using polycrylamide gel electrophoresis, and, as a result, 16 different patterns of isozymes were observed. Polymophism of isozymes patterns appears within species and more significant differences in pattern between species have been found. “Zymogram distance” was measured for each species pair and section pair. The ten species may be divided into 4 groups according to their “zymogram distance” and specific bands, which accords with the classical taxonomy of Juglans L.. Evolutionary relationship among species and rate of evolution for Juglans L. are discussed.

Key words: Juglans, Lsozyme