The nature reserves are often faced with the contradiction between resource protection and tourist activity. It is important to study the relationship between tourist activity and vegetation environment in nature reserves. Vegetation landscapes are not only important tourism resources, but also levers of harmonizing their ecological balance. This paper analyzes the relationship between tourist activity and vegetation environment in Dinghu Mountain, and evaluates the management level in the tourism region. Six indexes are used, including the sensitive level (SL), community landscape importance value (LIV), information index of species diversity (H'), negative species proportion (NSP), proportion of plants accompanied with mankind (PPM), and tourism impact index (TII). The result shows that there are some correlations and regularity between the TII and the evaluation indexes of vegetation environment, among the evaluation indexes of the vegetation environment quality, and among the factors of tourist impact index. The larger the SL is, the larger the H', PPM and TII are, and the smaller the LIV and NSP are. However, the larger the TII is, the smaller the LIV and NSP are, and the larger the SL, H' and PPM are. The TII is positively correlated to each factor, including rubbish impact index, damaging branches impact index, woods regeneration impact index, and meadow situation index. The regularity is that the larger the TII is, the smaller the dead sticks and humus thickness, meadow coverage, sapling number are, and the larger the damaging branches number and rubbish number are. These facts indicate the regularity of tourist activity has an impact on vegetation objectively, and this accords with the fact of tourism practice in Dinghu Mountain. Based on evaluation class of TII, the management level of tourism region in Dinghu Mountain is good and middle level on the whole nature reserve, but there are some dangers in some regions which need to raise the tourism management level further. Finally, the paper puts forward some management tactics in the tourism region.