The Accounting Information Systems (AIS) provide the knowledge with which to meet current challenges and opportunites. It has been one of the major subjects within the today’s globalization. Information technology plays a significant key role in companies’ daily activities. Databases and information are among a company’s most important assets that concern data reliability and securitiy and are relevant not only to accountants but also to all information systems professionals. AIS are a sort of a subsystem within the organizations’ Management Information Systems. Information technology plays various significant roles in businesses that tend to become more effective. Therefore we examined AIS as an important today’s development. The aim of this case study is to answer to the question ”what is the role of AIS in creating value in companies?”, and also to observe the use of AIS in creating value in selected large Turkish companies.