Abstract: In this paper,the author made a quantitative study on a spacial pattern of Paulowina-wheat intercropping a-groforestry system wiht the mathematical methods of GreyControl System taking 10 years as a rotation period with dif-ferent spacial density treatments,the author derived a model decision optimum spacial pattern of Paulowina-wheat agro-forestry system ,by using a multi-objective Grey Sitution De-cixion. It is concluded that:(1) with priority given to agricul-tural production,the optimum spacial pattern is 5×40m ;(2)with priortty given to forestry production,the optimum spaLcial pattern is 5×5m and (3) with priority given to agricultural and forestry production,the optimum spacial pattern is 5×20m.