In Croatia as well as in other countries, banking is one of the most profitable activities that, despite legal or economic constraints, continues to develop and monitor trends. Banks are obliged in their business to respect the norms and instruments of economic policy in the country in which they operate, but continually find the optimal solutions related to the most important thing - the capital of their customers. The solutions that banks are using in the recent times derive first of all from the modernization of the banking system, which means that the bank strives to offer its customers a permanent and future service that is at the same time quality, easily accessible and reliable. Therefore, in this paper we present the business of Croatian banking in the recent Croatian history, the evolution that we call electronic banking, define the concept of electronic banking and process protection mechanisms when using it. We list and explain the ways of authorizing in electronic banking such as tokens, smart cards etc. In the many news that brings us the modernization of banking, we will not miss out on and explain the advantages and disadvantages of using it. The main goal through practical work is to display and analyze the security of e-banking system, to start applying to the system, savings, payments, investments, etc. Erste Bank and Addiko Bank are the subject of research and analysis.