We have studied on structure optimization of Paulownia agricultural integrated system.The results showed that different year(A)of Paulownia wheat intercropping and the relationship between tree belt distance(X d)and wheat yield(Y)was Y =90 3290 1 9982 A +1 1924 X d 0 3349 A 2+0 2910 AX d 0 0032 AX 2 d ;the between tree coverage (X c)and wheat yield was Y =0 0406 XA 2 c +1 1539 X c +98 173(X c≤28%), Y=e (4 71516 0 005339X c) (X c>28%);wheat yield incre...