On the basis of "Qingdao government management in formation and aided decision system", this paper presents a new developmentand design principle for the oriented--manager forecasting application system: based on the general and classical forecastingmethods and modern computer technology, a system's integrated environment would beestablished to support managers to use these forecasting models effectively and understandingly. On this principle, the paper describes the design and practice of forecasting ap plication network system(FANS) in integrated environment.