This paper analyzed the ecosystem characteristics of the region which Baoiji-Tianshui highway bypassed, combining data on the road construction project bid with knowledge on the situation of each forestry centre distribution in Xiaolongshan. The first grade road-ecosystem region was divided into four parts: Maiji forestry centre ecology region, Dangchuan forestry centre ecology region, Baihua forestry centre ecology region, and Dongcha forestry centre ecology region. In the end, the Dangchuan forestry centre ecology region, which is passed by the Huashishan 1# tunnel, was chosen as the mainl region of this research. For this region, the plant community was investigated and the methods of “Quantity Statistics Analysis”, “Extended Nearest Neighbor Analysis”（ENNA）, and “Point Pattern Analysis” were applied. Furthermore, dominant species were selected and their spatial distribution pattern of the natural and manual (Larix kaempferi), zonal(Quercus aliena var) and non-zonal(Pinus armandii, Betula platyphylla) vegetation population type were examined. It is concluded that members of different plant communities in different scales have different spatial distribution patterns. For example, Quercus alienavar mainly showed random distribution in the 0-10m-scale performance, aggregated distribution in the 10-20m-scale performance, and uniform distribution in the 20m above-scale performance. In addition, the study will provide information on biological monitoring factors that can be used in comparative studies after the completion of the highway construction, as well as some methods for plant ecological remediation and vegetation landscape designing. It is the author′s belief that the scientific basis provided in this study can give valuable insights into finding more reasonable ways to protect the road-environment.