In this paper, Data Envelopment Analysis (DEA) model was applied to compare and ana- lyze the operating efficiency of 20 forestry listed companies in the stock markets of Shanghai and Shenz- hen. The statistic results showed that for most forestry listed companies, their operating efficiency reached DEA effective. However, the operating efficiency of several companies is mild invalid or mod- erate DEA invalid, which is due to the influence of pure technical efficiency or scale efficiency or both factors, and there exists increasing returns to...