This paper studied on spatial distribution and distribution patterns of species diversity along distance gradient of different forest communities in mountainous areas of the West Lake in Hangzhou, by using quadrat method, and TWINSPAN、β diversity indices and DCA、CCA ordination analysis. The results showed that: (1) 43 plots could be classified into six kinds of community types by using TWINSPAN and DCA. The habitat condition and species composition of different communities were both varied in those communities respectively. (2) With the increasing distance between communities, the Sorensen index tends to decline, but not always decline with regularity. (3) CCA based on the ecological important values and habitat factors of these 43 plots revealed that aspect, slope and slope-position, elevation and crown closure that affecting solar radiation and water distribution affect the distribution pattern of plant communities and quantitative of population respectively. In all, the forest community β diversity is mainly decided by its habitat condition variation and species dispersal.