Abstract: Taking the Baili Rhododendron nature reserve as an example to study the the community biodiversity of Rhododendron lilacinum.The method of field plant community investigations was used.A sample plot with the area of 10 m×20 m was investigated to study the community structure and diversity characteristics, in order to provide a referencefor the effective protection of germplasm resources and biodiversity of Baili Rhododendron.The results showed that, 1) there were 47 species of vascular plants belong to 24 families and 32 genera,and the dominant families in the community were Rosaceae and Ericaceae.Many families and genera had only one species.2)The vertical structure of the community consists of three layers,arborous layer,shrub layer and herb layer.R.agastumand Quercus fabriare were the dominant species and sub-dominant species in the arborous layer,the R.lilacinum was the dominant species in the shrub layer.