The subject of financial reporting transparency and its importance which has been more highlighted in recent years following unfortunate circumstances and created crises in world stock exchange and specially Black September in 1997, the event of September in 2001, disclosure of World Com, Enron, Xerox, Parmalat on the global level, and fall of Tehran Stock Exchange Index in 1383 caused the subject of financial statement transparency to become a necessary phenomenon and the necessity of stock exchange to allocate a greater share to itself. This study has been performed as below: Investigations concerning the relationship between tax reporting and financial reporting transparency.The subjects of the study consisted of different groups including Stock Exchange, Tehran Tax Affairs Organization, university professors, managers (companies), and certified accountants (auditors) of Tehran in 1389.The sampling method was based on ratio scale, and the sample volume was 150.The subjects were divided into five groups (the calculation procedure has been explained in the first chapter). To analyze the data and to indicate whether or not there is a relationship between tax reporting and financial reporting transparency in each participant group the inferential statistics of correlation coefficient was used and to show the difference between each pair of correlation related to these groups the inferential statistics of Z- Fischer was applied. The results of the study indicated a positive relationship between tax reporting and financial reporting transparency in that financial reporting transparency will be secured to a great extent if tax reporting is documented in addition to present financial reporting.