This research has considered the aspect of agency theory to present a suitable model for estimating audit fees. This research tries to examine the impact of two categories of general factors and representative costs that affect the risk, volume and complexity of the unit's operations, as independent research variables, and the dependent variable is the audit fee. The purpose of the research is pricing for auditing services in order to provide a model for estimating audit fees. In this study, general factors affecting audit fees are included: the mean logarithm of the total of all outputs operating profit, Distribution of interest deduction and Tax on assets, the ratio of receivables to assets and year-end financial and effective representing indicators on wages are: the ratio of total debt to assets, the ratio of non-executive directors to the total members, the ratio of the share of government entities, the ratio of the share of the first major shareholder. The main research hypothesis is the relationship between the cost of representation and audit fees, and for review this relationship multivariate regression is used . The information needed to test the hypotheses has been collected from listed companies in Tehran Stock Exchange for the years 2015-2016. The results of the research show that there is a meaningful relationship between the cost of representation and audit fees.