This paper discusses the vertical distribution of nutrients and dissolved oxygen in water column of Fuxian Lake, Combined with lake-test of multimetallic nodules mining system, we also discuss the influence of human disturbance to lake water quality.Based on the results, we find that the distribution of nutrients and dissolved oxygen obviously displayed seasonal variation and was controlled by climatic parameters.The re-suspended sediment caused by moving of mining system on the 1 ake-floor, will influence the distribution of nutrients, especially in near bottom water which is caused by re-releasing of nutrients from sediments previonsly adsorbed on sediment.Therefore, we should pay more attentions on sediment when we assess the influence of human activities on lake environment.