Researching the domain of competitive advantage, are carried out at the levels of entity or industry. But a broader perceptive which is the investigation of competitive advantage at national level and more comprehensive level has been rarely taken into account by researchers. To solve this problem, in this article, relying on a efficiency – oriented approach and paying attention to the inputs of each country. The efficiency of each country is examined in competitive advantage. As a whole porter diamond model defines, 6 input elements, for examining competitive advantage of countries. Considering the previous research which is done on this model has resulted in gratification of this model, the researchers have tried to calculate the efficiency by selecting a suitable data envelopment analysis approach. Regarding the selection of 112 countries and 12 input criteria and 2 output criteria, it was shown that having 68.67% of efficiency Iran is ranked 70th. Examining the efficiency a during 2000-2003-2006 results in a continuity of efficiency significance. In this way, Iran, by a great growth of efficiency which is the result of the decrease in Manufactures imports and the increase in direct foreign investment has obtained the efficiency in 2006.