This study is aimed at investigating the effect of the industry concentration on the internet-based compulsory information disclosure with respect to the control variables of the firm size, industry, profitability and leverage and independent or non-executive independent board. Statistical population of the study is the firms accepted in Tehran Stock Market, 230 firms were selected omission during 2010-2011 period as the statistical sample and their information was investigated. In this study, the data required to test research hypotheses were collected by a field method through financial statements and notes associated with stock firms and accepted firms web site, then they were created and processed in the form of databases in excel and finally the data and research variables were analyzed using EVIEWS Software. In this study, the researcher analyzed the effect of industry concentration on the information compulsory index. The results show that the industry concentration, the firm size, profitability, leverage and the other industries except the energy and service sector have a significant effect on the compulsory information index but there is no effect for the independent or non-executive independent board.