In the introductory part of the thesis the problem and the subject matter of the research and the research hypothesis are presented, followed by a theoretical review of the audit whose main task is to examine the objectivity and the reality of the basic financial statements. According to the law, the authorized auditors, independent auditors, joint audit offices and auditors society. Below, the audit demand, the auditing services market and the professional framework of the audit profession are explained. The next chapter deals with the regulatory framework of the auditing profession in Croatia. This chapter defines taxpayers and legal auditors as well as explaining the role of the Croatian Chamber of Auditors as well as oversight of audit firms and auditors. In the second, empirical part of the paper, hypotheses were tested, with the main emphasis being on determining the level of transparency in the auditing services market in the Republic of Croatia. The research was conducted on the data collected on companies listed on the Zagreb Stock Exchange for the period from 2015 to 2017. In addition to the hypothesis hypothesis, insights into certain characteristics of auditing companies, such as the level of income, the business outcome and the number of clients, were also obtained.