Investigate the relationship between Biorhythmic cycles and Error financial decision making in Tehran stock exchange

Make decision is one of the important factor in organization and the managers who act optimization in it can be guide the organization toward successfully. In this research we investigate the relationship Biorhythmic cycles that influence on decision making of investing managers on investment funds in Iran s capital market. The biorhythm components include physical cycle, Intellectual cycle and six sense and the components if error financial decision are compare, commitment, information bias ,cognation bias And rare effect . The research method is descriptive and from the aim standpoint it is applicable. The sample estimate by Cochran formula and the questionnaire distributed between them randomly. Reliability and validity controlled, and the reliability based on Cronbach alpha is 0,88 .The hypothesis test by spearman correlation and based on it there is significant relationship between physical cycle, six sense and error financial decision. Finally to answer the research question we use the structural equation to show the relationship between error financial decision and biorhythm cycles that showed biorhythm cycle effect on error financial decision is 0,33 .for ranking the component of error financial decision we used the Friedman test .In the last we offer some suggestion for researchers, organization, Investment Funds and Managers of Investment funds.