Abstract: On the basis of investigation, 22 genera, 48 species, 1 variaty and 3 forms of legumes in Changbai mountain are taxonomically studied (except cultivated species, Table 1) in present paper. The ecological habit, ver-tical and geographic distribution of each species are also presented (Table 1). Most of the legumes in this area are heliophilic mesophytes, 6 species meso-hydrophytes, 6 species meso-xerophytes, and 3 species growing on the cold and moist alpine turdra with short frostless season. What it is notable in vertical distribution (except semi-wild species) is that only 3 species i.e. Oxytropis anertii, Vicia ramuliflora f. baicalensis and Hedysarum ussuriense are distributed on the alpine turdra from 2000-2600 m above sea level, 4 spec- ies, i. e. Hedysarum ussuriense, Vicia ramuliflora f. baicalensis, Vicia venosa and Trifolium lupinaster in the Betula ermanii forest zone 1700-2000m above sea level, 5 species, i. e. Vicia venosa, Vicia ramuliflora f. baicalensis,Vicia cracca,Trifolium lupinaster and Astragalus uliginosus are in the Picea-Abies forest sub-zone 1350-1700m aboye sea leve, and more than 40 species, making up 90.9 percent of the total wild species are growing in the mixed forest zone of Pinus koraiensis and broad-leaf trees which is the major zone where the legumes are growing in Changbai mountain. The secondary forest zone lower than alt. 500m is the major place where the invaded meso-xerophytes are grow-ing. In geographical distribution, most of the legumes in Changbai moun-tain are distributed in the temperate to subcold zone, only a few species reach Europe, North America and southern China. 2 species even reach tropical area of Asia, Africa and Australia. In floristic composition, 18 species belong to China-Japan component, 12 species Sibirica component, 3 species Europe-Asia component, 3 species Changbai component, 2 species Changbai-Dahuri component, 2 species Asia-N. America component, 1 species holarctic component. 1 species Arctic component, 2. species tro-pical Asia component and 1 species paleotropical component. It is obvi-ous that China-Japan component is the major composition (40.9%). The fact indicates that there is a close relation between Changbai mountain and Japan in the floristic occurrence of legume. Sibirica component takes the second place (27.3%) the rest components are less important. It is notable that there is no endemic species of China, only one endemic species of Changbai mountain but shared by China and Korea. Changbai mountain is the center of Changbai plant region, however, "component of Changbai plant region" is only 3 species. Most of the components are China-Japan or related to Asia, Europe and North America. It is easily concluded from.the fact that the flora of legume in Changbai mountain is old in the his-tory of phylogenetic origin and distribution. The symbiotic nitrogen-fixed abilities of 27 species belonging to 14 gen-era are tested. These plants grow in the different vertical distribution zones (alt. 500-2600m) on Changbai mountain. The results show that the nodules of all plants tested haye the nitrogenfixed activities, and different species have different activites. However, there in no correlation between the nitrogen-fixed activities and the elevation of plant distribution. It may be potentially important that, of the 27 species, 5 show higher nitrogen-fixed activities than others. They are Medicago sativa, Lathyrus vaniotii, Guel-denstaedtia verna, Kummerowia stipulacea and Melilotus suaveolens. The other four species, i, e. Astragalus membranaceus, Vicia pseudorobus, Vicia eracca and Lath-yrus palustris var. pilosus also show higher activities. These species as well as their symbiotant-rhizobia have prospects in exploiting and using of natural resources. More attention should be paid to them and more study is also needed.