A large number of deserted copper mine tailings dumps of different age exist in Tongling,East China,covering a large area of land.In order to understand effect of natural plant communities on enzyme activities in the soil,six dumps different in age were investigated.The results show that the plant communities naturally colonizing on the wastelands markedly increased enzyme activities(urase,arylsulfatase,alkaline phosphatase and dehydrogenase)in the upper layer of the tailings(0~5 cm).But the effect varied with the type of the plant communities.Enzyme activities in tailings under the Hippochaete ramosissmium-Zoysia sinica community and Impreta cylindraca community were higher than under the Cynodon dactylon community and Zoysia sinica community.Of the 4 soil enzymes studied,alkaline phosphatase and dehydrogenase were higher than urase and arylsulfatase in activity.Data analysis indicates that there was a significantly positive correlation between enzyme activities and chemical propert ies(including humus,total nitrogen,available phosphorus,available potassium and electrical conductivity), but a significantly negative correlation between pH values of the tailings and act ivities of arylsulfatase and dehydrogenase.The surface layer of tailings heavily oxidized exhibited extreme infertility and extremely low activities of soil enzymes.