Abstract: Since the late 70's, a kind of computer application system used to aid decision making -Decision Support System (DSS) has gone into the practical application stage abroad, with the development of computer technology, since 80's, it has been getting more and more attention from the researching department in applying field of Management Science and System Engineering in China. Now, the theorical study for DSS primarily focuses on it's interface system. This paper describes a designing method of DSS's interface, which was proposed by author in the development of Forestery Ecology Economics DSS. It can be applied to the society, economics, agriculture, ecology or engineering system.