This paper investigates the effect of adjusted DuPont ratio and its components on investors' decisions in short and long term. The primary objective of this study is to find the effect of adjusted DuPont ratio and its components on herding behavior of investors in one and several year period. Hence, 85 corporations as the member of Tehran stock exchange over the period 2006-2011 are selected. In order to recognize the herding, by market index consideration, the herded β and in order to hypothesis validity SPSS software and multivariable linear regression have been used. As the results of this study indicate, the adjusted DuPont ratio and its components have more effect on investors' decisions in short term but in long the period, the effect of this ratio on herding investors' behavior are reduced. Furthermore, from the two components of adjusted DuPont ratio, profit margin has more effect on investor's decisions.