SUMMARY
The aim of this study is to investigate the relationship between institutional investors, financial constrains and fluctuations in companies growth. The present study is a library and analytical-causal study done through the panel data analysis (panel data). In this paper, financial information of 107 companies listed in on Tehran stock exchange during 2009 to 2014 was examined (642 companies – year). To analyze the data obtained, SPSS 22, Eviews 8.1 and Minitab 17.1 software were used. The results confirming the first hypothesis suggested that there was a direct significant relationship between percentage of institutional investors and fluctuations in companies' growth. Also cording to the analysis conducted in connection with the second hypothesis, we came to the conclusion that there is an inverse and significant relationship between financial constraints and fluctuations in companies' growth. In the end, results obtained in relation to the confirmation of the third hypothesis indicated that there is no significant relationship between financial constraints resulting from the percentage of institutional investors and fluctuations in companies' growth.