According to statistical material and analytic data of soil related, the farmland nutrients balance and the dynamic changing tendency of the main soil nutrients from 1985 to 1999 in hilly areas in the middle basin of Sichuan were discussed through Zitong, Zizhong and Qianwei counties. The results showed that after 1990, the nitrogen in farmland was changing from equilibrium to surplus, it was surplus over 35 percent; the phosphorus was surplus over 40 percent; the potassium was deficient all along with high proportion, it was deficient nearly 50 percent. Meanwhile, comparing the content of soil nutrients between 2000 and the second soil investigation, the effect of farmland nutrients balance on soil nutrients level was discussed also, thus the regulating ways relevant was given for sustainable farmland development.