M.A. Thesis:

audit quality mediate the effect of auditor tenure, audit fee

Abstract This research aims to investigate the auditor's tenure and audit fees with the role of mediator of audit quality in Tehran Stock Exchange. The impact of the duration of the audit tenure on audit quality in literature and audit research has been widely discussed and presented with completely different results in the form of two theories, the auditor's expertise hypothesis, and the auditor's independence hypothesis. The auditor's expertise hypothesis believes that the quality of the audit will be improved by increasing the duration of the audit tenure. On the contrary, the auditor's independence hypothesis said that the quality of the audit will be reduced by increasing the duration of the audit tenure. This research was conducted among 119 firms for a five years period (2012-2016). The data obtained from the firms studied, were analyzed by the Eviews software. The results of the research showed that there is a direct and significant relationship between the auditor's tenure and the quality of audit, but there was a negative and significant relationship between the auditor's tenure and audit fees. Also, there was no relationship between audit quality and audit fees in this research, and audit quality failed to mediate the relationship between audit tenure and audit fees.

Keywords: Keywords: audit fee, audit quality, auditor's tenure, Tehran stock exchange