The key for using system engineering to tackle a small watershed comprehensivly is to form a mathematic model. How to formulate an optimiying model is a problem hauing to study urgently in order to obtain the overall benefity both under local condition and economical situation. The paper followed a planning using an integration of goal func tions for controlling Xing long Small watershed, Kesan county, Hai long Jiang Province to approach the efficiency of the method.Application of the method made the four goals, pure incomes, investment, soil and water conservation and food production maximum or minimum satisfingly under controlling the small watershed.