One of the most important issues in finance is investor's behavior in security markets. Standard Finance says that economic agents are rational and behavior finance emphasizes on biases by investor when they are making decision. According to research conducted at the Tehran Stock Exchange (TSE) , investor have four types of behavior in which are : Rational , Herd behavior , Heuristics and Overreaction . The purpose of this paper is evaluation and ranking the behavior of investors in the Tehran Stock Exchange by analytic network process (ANP). For this study we used the super decisions software for evaluation and ranking and Judgment of experts for Paired comparisons. The results show that individual investors have 40 percent herd behavior in their decisions also 33 percent of individual investor's decision is rational and 22 percent of individual investor's decision is overreaction and 5 percent of individual investor's decision is heuristics. This research indicates that almost 35 percent of investors in Tehran Stock Exchange is influenced by factors relating to the Stock Market Such as transparency, market efficiency, market depth and etc.