Abstract: Based on 15-year's investigation,it was found that there were 142 species of ornamental tree species belonging to 74 genera of 36 families,including 11 endangered tree soecies under national protectdion which accounted for 7.75 % of the total tree species in the nature reserve.From the viewpiunts of ornamental characters,the flower plants,fruit plants and foliage plants took the percentages of 45.07 %,59.15 % and 33.80 %of the toral respectively.From the viewpoints of ornamental usage,the plants for garden landscape,potted landscape and shrub bedding took the percentaged of 40.30 %,37.83 % and 33.10 % of the total respectively.Abour 69.90 % of the tree species were of the type of northern temperate distribution zone.The dominant families were Rosaceae,Caprifoliaceae and Aceraceae,etc.Some other applications of ornamental tree species were also introduced.