Abstract: Longshan Forest Park which is an isolated mountain in central Hunan province,is located at the floral boundary of Central China and East China,with various ecological conditions and different vegetational types.There are 1486 wild species of seed plants belonging to 687 genera of 158 families in this area.The whole floral natures of seed plants belong to mainly temperate,mixed with abundant tropical areal-types,it shows distinct transition chartecteristic between the tropic and temperate,but in families and genera level,there are higher proportion in the tropical areal-types,it means that the natures of tropical geographic affinities are distinct in this area.Otherwise,the dominant large families and large genera are majority position in statistic of floral composition.In studies of relationship of floral geography,comparing to some neighbor areas in Hunan province,the flora of Longshan are more similar to those of Gaowanjie in Guzhang county by the higher similarity between the both areas in species and genera and family statistic,but there is a low similarity between Longshan and Nanyue Hengshan.It demonstrates that the isolate mountain of Longshan is only independent in landform,is not in their flora,and absent in endemic floristic elements.Based on above mentions,the flora of Longshan are more impacted by the flora of Wuling Mountain.Thus,their flora shoud be belong to a part of the floristic region of Central China,with some transitional floristic characteristics between Central China and East China.