With the native villagers attending,100 households were investigated to evaluate the diversity of plant species and varieties which were managed and preserved with participatory biodiversity appraisal(PBA) in Shuangqiao,a drinking-water protection region of Kunming.The main results are as follows: 70 plant species including 150 varieties of field crops,ornamental and virescence plants,were cultivated and utilized by 100 households.And there is plenty diversity of plant resource,having 31 species and 105 varieties of field crops,39 species and 45 varieties of ornamental plants and virescence plants.Field crops,such as corn,potato,pea,tobacco,wheat,cabbage and horsebean were extensively planted and cultivated.On the contrary,ornamental plant and virescence plants were rare.It was suggested there was a great difference among household levels of planting and utilizing plant resources number and diversity.Rich degree and biodiversity of plant species and varieties which were managed and utilized by 6% households was high,so the 6% households took more contribution to the conservation of plant diversity.