To analyze the efficiency of the agro-ecosystem of Dongting Rim in Hunan Province, this paper adopted the emergy theory to study the agricultural output of this region during 2001 to 2010. The results showed that the value of regional agricultural emergy output increased by 44.68% to (6.50 E) sej, but lower than the growth of non-agricultural industry output. Compared with 2001, the emergy output of planting industry was (4.10E) sej in 2010 which occupied 63.09% of the total agricultural emergy output and got an increase of 2.93 percentage points, while the emergy output of stock farming got a decrease of 2.87 percentage points. The growth of fishery emergy output was not in conformity with the characteristics of Dongting Rim in Hunan. From the contrast between emergy output and economic output, we could find that the economic return ratio of planting industry and fishery industry were lower than those of forestry industry and stock farming industry, which indicated that it is necessary to improve the economic benefits of planting industry and fishery industry which were the traditional industries with advantages of the Dongting Rim in Hunan.