Located in the southeast of Hanyang Prefecture of Wuhan, Moshui Lake is a small-median-size lake with an area of 3.35 km².Being important water resources in local areas.it plays a k,y role in aquatic farmings irrigation and water supply.In the past So years, nearly 8000 tons of waste water per day was discharged into the lake as a result of industrial, agricultural development and population increase.The water quality in the lake is seriously deteriorated, which leads to growing eutrophication.Some parts of the lake are even getting dark or stenchcd.The neighboring people's health and the entertainients of Wuhan Zoo are threatened consequentially.To meet the urgent needs of comprehensive regulation, control and planning for Moshui Lake9 we set up here a N/P water quality model after the pollution sources in Moshui Lake surveyed and its water quality assessed.First Moshui Lake is divided into 5 subareas, each of which contains several small parts.Then in each subarea a scattered structure of N/P model is built,and the parameters of each model are identified respectively.the accuracy of calculation by means of PC-1500A is satisfactory.Finally the systematical theory is introduced in the analysis.The whole calculation is operated by programming computer language.The model building and parameter identification are advantageous in this method, so it is hopefully convenient for more practical applications.