Abstract: Enterprise efficiency research is of great significance for optimizing the capital layout structure and enhancing the efficiency of enterprise supply. Using CNKI as the data source and Endnote， Bibexcel，Ucinet and other text classification tools， this paper makes a co-word network analysis of the representative researches on enterprise efficiency from 2006 to 2015 and clarifies the branches， hot spots and trends in the research structures.The results show that: the 17 knowledge nodes with degree centers higher than the mean such as DEA， industrial enterprises and so on are the hotspots of enterprise efficiency researches; the 17 information connectivity points with high intermediate centrality and closeness centrality such as DEA， enterprise performanceand so on are the high incidence areas of new theories and new methods in the future. Enterprise efficiency research forms the four research structures of efficiency concept， enterprise type， measurement method， and influencing factors (or economic consequences).This systematically provides a structured context for subsequent researches.

Key words: enterprise efficiency, co-word network, text classification, research structure