The distribution patterns of plant biodiversity were studied in the two kinds of ecoto-nes between forests and swamps in the Changbai Mountains,by using transect and Shannon-Wiener index methods,in order to reveal the distribution patterns of plant biodiversity along the moistened environmental gradients or among vertical layers of communities in the Alnus hirsuta,Betula platyphylla-swamp ecotone or Betula platyphylla-swamp econtone disturbed by human activities.The results showed that:① The horizontal distribution patterns of plant biodiversity ap-pears a protruding shape along the A.hirsuta,B.platyphylla-swamp ecotones.Plant biodiversity of this kind of ecotone community is 2～3 times that of nearly swamp community, and 1.5 times that of forest community.On the contrary,it presents a concave shape,and plant biodiversity is only 80% that of nearly swamp or forest community in the B.platyphylla-swamp ecotones disturbed by human activities.②The vertical distribution pattern of plant diversity presents a "pyramid shape"in A.hirsuta,B.platyphylla-swamp ecotones,the ratio of which is tree layer:shrub layer:herbage layer being 1:3:5.In contrast,no"pyramid shape"occurs in B.platyphylla-swamp ecotones disturbed by human activities,the ratio of which is tree layer:shrub layer:herbage layer being 1:0.4:5.So human induced disturbanc has great influence on distribution patterns of plant diversity in the B.platyphylla-swamp ecotones.