The performance of an internal audit department must function in a manner that is in accordance with applicable professional standards such as Standards for the Professional practice of Internal Auditing and the quality of the internal control systems. This study looks at the internal auditing practices and performance of internal audit departments. Using data from 250 auditing practitioners, this study suggests that independence, scope of audit work, audit reporting, audit programs, management of internal audit department, performance of audit work, audit reviews, objectivity and professional proficiency are important internal auditing practices from the perception of internal auditors. This study also suggests that risk assessment, control activities, control environment, information and communication and monitoring are important quality of internal control system from the perception of audit committee. From the findings, 50% of the respondents strongly agreed, 27.5% agreed, 12.5% were not sure, 10% disagreed and none of the respondents strongly disagreed with help management of the organization in its present and future growth. Provide advisory services to provide assurance to the CAO about operation had 25% of the respondents who strongly agreed, 45% agreed 5% were not sure, 10% disagreed and 15% strongly disagree. The study also shows that the management of internal audit department, performance of audit work, audit program and audit reporting significantly influence the risk assessment of the quality of the internal control system.