Abstract: Hailuogou is the key area of Gongga Mountain Nature Reserve, and the area of virgin forest is more than 70 km². Plant diversity of Hailuogou was investigated from May to September, 1999 and in July of 2006. Based on the statistics of transects and plots in the vertical sequence of the vegetation, and combined with the related literatures, the higher plants were composed of 78 families,352 genus and 1 432 species (including lower units) in Hailuogou. The vertical differentiation of vegetation type showed the belt-type of different space,and the vegetation types were comparatively abundant.