Word revision comes from latin word „revidere“ which means to look, to see again, and therefore, it is considered as a subsequent review and review of business processes and conditions. Revision is said to represent objective comparations made with specific criteria, while respecting the compliance between executive jobs and criteria, forming of a court of compatibility degree and reporting findings to competent persons (American Accounting Association – AAA ; Fraser i Aiken, 1981:118). It gives an answer to the question of wether financial reports and financial position of enterprise are in harmony with acceptable accounting and financial principles. Audit role is to protect the interest of capital owner, and to reduce the risk of investment by raising additional capital. An audit of information systems can be internal or external, and it is conducted by experts specialized in that domain who have extensive accounting knowledge and experience. Auditors by concluding their business create financial reports that help the client to make decisions. Financial reports are created on the financial information basis. The annual financial reports include balance sheet, profit and loss account, cash flow statement, reports about capital changes and financial report notices. Auditors nowadays benefit from the choice between several implementation methods, among which CobiT method, ITIL method, ISO 17799 and ISO 27001 standards are the most famous. Each auditor will decide, based on the current state and on their own practices, which method they will apply to a particular company. Audit process can't be unlimited, so it's important that its activities have a limited duration. Audit procedure of Information System contains steps or stages that follow one another. Besides, individual steps are carried out at the same time, depending on the nature of the information system itself