“Audit Quality” is not easy to define because of many diverse factors affecting quality. According to the consultation paper of the International Auditing and Assurance Standards Board (IAASB), audit quality is the significant issue that requires more considerable attention. Understanding how audit quality is important requires investigating audit quality factors more precisely. So, the present article aims to review and summarize the different audit quality factors, comparing the results achieved by the related recent studies. In this regard, as well as the well known audit quality factors such as size, industry expertise, auditor tenure, audit fees, non-audit services and auditor reputation, auditor specifications, were found to be able to affect audit quality significantly. Moreover, such factors can affect each other while affecting the audit quality directly.