The purpose of this study is to propose vegetation management devices through analyzing the actual vegetation, flora, plant community structure and soil chemical concentrations in Weolmi urban nature park, Incheon. The actual vegetation of Weolmi Park in various areas is composed of urbanization area(2 types, 25.9%), landscape planting area(4 types, 16.1%), grass and marsh area(5 types, 7.6%) and mountain forest areal(14 types, 50.4%). The flora is composed of 295 taxa with 80 families, 253 species, 35 varieties and 7 formas, and among them there are 16 naturalized plant families, 39 species, 3 varieties. In reflection of size, the number of the species seems high but most of the them are under influence of human disturbance. Nine survey plots of plant community structure are classified into two groups. One is the semi-natural plant community(Prunus sargentii-Acer palmatum, Quercus accutissma-Prunus sargentii, Quercus serrata-Quercus accutissma-Prunus sargentii, Prunus sargentii, and Zelkova serrata-Prunus sargentii) that migrated finn the planting forest to the natural forest and the other is planting forest(Pinus koraienssis-Pinus thunbergii-Abies holophylla-Chamaectparis obtusa, Prunus sargentii, Pinus thunbergii-Alnus firma, Zelkova serrata). The average pH is 4.65 which means the soil acidity is quite high. The concentration of K, Ca, Mg and base saturation is very low. It seems that the environmental pollutants from Incheon Port and industrial plants near by survey site and long-distance transport of air pollutants from China made the soil condition worse. On the basis of the results above, six vegetation management devices are suggested: 1) removing the hazard plants(Pueraia thunbergiana and Humulus japonica), 2) natural landscape management of the middle and long term, 3) increasing species diversity, 4) Robinia pseudoacacia management, 5) keeping the naturalized plants from being distributed any further inside the mountain forest, 6) improving soil acidification.