The soil enzyme activities and nutrients of three types of wetland(Carex lasiocarpa,Calamagrostis angustifolia and island forest wetlands) in Sanjiang Plain were investigated.And the relationship between soil enzyme activity and nutrients and the relationship among enzyme activities were discussed.The results indicated that soil enzyme activity and nutrients differed obviously among different wetlands in Sanjiang Plain.The content of soil organic matter,total nitrogen and available nitrogen were in the order of Carex lasiocarpa wetland>Calamagrostis angustifolia wetland >island forest wetland.And the activities of invertase,urease,amylase,catalase were in the same order.The acid phosphatase activity was in the order of island forest wetland>Carex lasiocarpa wetland>Calamagrostis angustifolia wetland.However,the activity of cellulase was in the order of Carex lasiocarpa wetland>island forest wetland>Carex lasiocarpa wetland.Through Pearson correlative analysis,the activities of urease,amylase,catalase were significant related to soil nutrients.And there were significant correlation among the three enzymes.Therefore,the activities of urease,amylase and catalase were possible to predict the soil nutrients.