This study aims to investigate if the mandatory adoption of the IFRS by the Brazilian companies listed in BM&FBovespa has made an impact on the audit fees. The final sample was made by 151 companies, between 2009 and 2012. To restrict the relations, other control variables of the size of the companies, of the turnover of auditing companies and of the quality level of the published financial statements were listed. The results made evident that the mandatory adoption of the IFRS represented a significant increase of 20.71% in the auditing fees. It has also been noticed that a positive relation between the auditing fees charged by the services and the size of the companies. However, the rotation of the auditing companies has generated a negative impact, reducing the fees paid to the independent auditors. Related to the quality of the financial statements, it was not verified a statistically significant relation.