Audit is a system of inspection by the auditor of the financial statements in determining the quality of the financial statements. Any audited financial statements by an auditor, then the company shall pay the fees for the audit services performed. In general, the purpose of this research is 1) to analyze the effect of inherent risk on audit fees. 2) to analyze the effect of control risk on audit fees. 3) to analyze the effect of detection risk on audit fees. 4) to analyze the effect of company size on audit fees. 5) to analyze the effect of internal audit on audit fees. The purpose of this study is to examine the influence of audit risk, company size and internal audit on the audit fees. This research was conducted by secondary data, with the number of population in this study as many as 95 companies. This research used sample of trading companies, services and other investment which are listed in Indonesian Stock Exchanges during 2013-2015. The number of trading companies, services and other investment in this study were 12 companies with 3 years observation that acquired by using purposive sampling method. Hypothesis testing in this study using multiple linear regression model. The result of data analysis or regression result shows that simultaneously audit risk, company size, and internal audit have influence to audit fee. While the partial results of this study indicate that 1) inherent risk has an influence on audit fees, 2) the control risk has an effect on audit fees, 3) the risk detection risk has an influence on audit fees, 4) company size has no effect on audit fees, and 5) internal audit has no effect on audit fee. This research shows that the existence of Audit risk will demand high audit fee. While the company size and internal audit is not influential does not demand the existence of high audit fees.