Abstract: This paper studied the characteristics of natural plant species influenced by urbanization and fragment by analyzing the flora of the remnant nature vegetation in Sheshan area, Shanghai. According to our collection and identification, there are 350 species and varieties, 235 genera and 85 families of wild seed plants, which can be divided into 13 types and 10 subtypes in the geographical distribution patterns.The results are as follows. There are remarkable relations between species and the area of each hill.The flora on Sheshan has a greatly close relation to that on Mt. Tianmu. Compared with plant lists in 1950s, there are 178 nature seed plants undiscovered, most of which are perennial herb.

Key words: flora, island habitat, fragment, dynamic change, Sheshan, flora, island habitat, fragment, dynamic change