Mohsen Dastgir - The professor of accounting group of Azad University of science and projects of Isfahan.
Hamidreza vakilfard - The professor of accounting group of Azad University of science and projects of Tehran
daruosh foroghi - The professor of accounting group of Isfahan University
Norouz Nourolahzadeh - The student of PHD of a counting of Azad university of Science and projects of Isfahan , responsible writer

At this article, the effect of important factors have been studied an interest management constraints and market reactions to unexpected interests at Tehran stock papers. Because of gaining mentioned goal and answer to research questions, four hypotheses have been codified. For testing of the project hypothesis, we have used the multi-factors regression analysis and financial data of sample of 89 firms between 2001-2010 years. The project findings show baht percent of unusual yield in comparison to positive unexpected interest for firms with interest management constraints is more that firms with flexibility at interest management it s contrary at negative unexpected interest. The investors show more confidence to reports and statements of interest of inflexible companies of management.

interest management constraints, unexpected interests, unusual yield, unfeasible firms, firms what flexibility at interest management