Abstract: The species composition, plant functional groups, community characteristics, and diversity index were investigated through building natural restoration. The Cynodon dactylon community and five kinds of mixture-planting plots of shrub and herbage on the Bi-Tong Expressway typical slope, and species similarity between different plots was analyzed. Plants of Leguminosae, Gramineae and Compositae occupied a fairly large proportion and played important roles in the reforestation plots. The mixture-planting plots of shrub and herbage could be divided into three patterns based on the change of dominate species. C. dactylon grassland (300-400 plants/m²), intergrowth land with C. dactylon and Medicago sativa(500-600 plants/m²), and M. sativa grassland (700 plants/m²). The density, coverage, height and biomass of reforestation communities tended to decrease and then increase as the density of herbage became higher. The maximum value was 700 plants/m². The species richness (Margalef index),plant diversity (Shannon-Wiener index), and Pielou evenness index tended to increase, to a density of 500 plants/m² then decrease. As the density of herbage became higher, species similarity between different plots and natural restoration tended to decrease and then increase, indicating that the composition of artificial restoration, not the herbage density, decided the community composition. The density had no serious effect on coverage, height, biomass and diversity of reforestation communities when the density was over 500 plants/m². The cost should be reduced and the optimum effect of restoration achieved by choosing the appropriate proportion of species and density.