This article focuses on identifying the essential factors that affect the audit quality and proposing some implications of the policy to contribute to the enhancement of the social trust in Vietnam audit profession. The pressure on the certified and reliable financial information is a key challenge to stimulate auditors to improve audit quality. The study reaches its objective by analyzing the point of views from survey participants (CPA and independent auditors) by using questionnaires and interviewing in combination with abroad and domestic references. The authors have collected 102 responses from professional staff working in auditing firms in Ho Chi Minh (HCM) city. Through evaluating the reliability of the scale, exploratory factor analysis (EFA), correlation analysis and multiple linear regression analysis, the research model shows that there are six factors affecting the audit quality. They are (1) professional ethics of auditors, (2) professional capacity of auditors, (3) quality of external control, (4) internal factors belong to auditing firms, (5) audit fees and (6) size of auditing firms.