The esterase isozyme in tissue of wild legume plants were separated by horizontal starch gel electrophoresis. Extracts used in this study were prepared from fully expanded young leaf, cotyledon and radicle of seedling and root-nodule of Glycine sola, Vigna vexillata var. tsuscmensis and Trifoliwn repens. The results are as follows; 1. Each tissue examined had a characteristic banding pattcrn. Number of bands in each species, G. soja, V. vexillata, and T . repens, were 14, 8 and 1 1 bands, respectively. And difference in esterase isozyme bands were greater from tissue to tissue than difference between habitat. 2. Est-I, Est-2. Est-3 and Est-4 in G. soja, Est-I in V. vexillata and Est-l and Est-2 in T. repens showed strong cnzyme activity than other enzyme. 3. Esterase isozyme variation in G. soja and T . repens showed more variety than V. vexillata. This is resulted from many genotypic differences within species. 4. The main enLyme among thc esterase isozyme were Est-I. Est-2, Est-3 and Est-4.