The internal audit is conducted to help the management. The weakness of the management is disclosed. The external audit is conducted to help the shareholder. The rights of owners are protected. The appointment of internal audit is made by the management. The appointment in external audit is made by the shareholders. Internal audit is the part of internal control.
External audit is the not the part of internal control.The internal audit can suggest improvement in internal check system. The external audit can not suggest improvement in internal check system. The internal audit can perform his duties under the terms of appointment. The management can limit the scope of work at any time. The external auditor can perform his work to terms of appointment and other prescribed law. The scope is very wide. Internal audit is an employee of the company. He is not an independent person. External auditor is not an employee of the company.