Abstract: By the methods of emergy, this paper studied the input and output, working efficiency, and environmental loading of the agro-ecolomic system in Shanxi Province in 2005. The results showed that in 2005, the agro-ecolomic system in Shanxi still stayed in the period of traditional agriculture, which mainly depended on manpower and environmental resources. The emergy investment ratio (EIR) was 1.07, emergy yield ratio (EYR) was 0.99, and environmental loading ratio (ELR) was 6.55. In the structural adjustment of agriculture, stockbreeding had made great strides forward, but grain crops other than rice and wheat, vegetables, and fruits still had smaller emergy yield and were far from becoming dominant industry. The efficiency of the agro-ecolomic system was lower, and its environmental loading press was bigger. For the future, the surplus labors in agriculture in Shanxi should be shifted continually to other industries, and the high quality emergy such as agricultural science and technology should be increased to improve the use efficiency of environmental resources and the input and output of the system emergy.

Key words: soil porosity, forest and grass measure, soil nutrient, soil microorganism, soil salt content