The Republic of Croatia, as the youngest member of the European Union, which became a full member on July 1, 2013, submitted a request to the authorized bodies of the European Union in July 2019 to introduce the Euro as an official currency. Having expressed a desire to introduce the Euro, Croatia finally became a full member of the Economic and Monetary Union (EMU) on January 1, 2023. However, before submitting the Euro, it was necessary to adjust the economy, that is, to ensure the conditions for a smooth, safe and transparent process of introducing the new currency. This is a crucial topic at the moment, which is reflected in the fact that the Republic of Croatia introduced the Euro less than a year ago, and it will surely occupy the attention of the general public for the next few years. This thesis aims to present the entire process of replacing the Croatian kuna with the Euro, the legal regulations of the process itself, the planned way of recalculating the funds in the accounts and the supply and exchange of cash of the old kuna currency for cash of the new euro currency. The ultimate goal of this thesis is a better understanding of the process of replacing the Croatian kuna with the Euro.