Abstract: The metal mining industry’s growth has slown down in the recent years due to a new round of cyclical adjustment.Considering long-term weakness of iron ore prices and production capacity expansion of foreign mining giants,domestic iron ore production enterprises face a severe challenge.In order to reduce dependence on imports and participate in iron ore pricing,China’s iron and steel enterprises has increased investment on mergers and acquisitions of oversea iron ore resources.The paper uses the method of data envelopment analysis (DEA) to evaluate the operating efficiency of Australian listed Iron ore enterprises from the year of 2011 to 2013,based on the output oriented CCR and BCC model.It turned out that the efficiency of Australian Iron ore industry is low;most of the iron ore enterprises are DEA inefficient.According to projection analysis of DEA to adjust inputs and achieve effective DEA by taking the company of FMG as an example.Finally,this paper explored the way of selecting iron ore firms in overseas and improving operation efficiency after merging for Chinese enterprises.