The aim of the paper is primarily to explain the significance and analytical meaning of the common euro currency and the nominal convergence criteria and analyze them theoretically and empirically on the example of the Republic of Croatia. The advantages and disadvantages of introducing the euro into the Republic of Croatia will be considered. From the previously defined goal comes the subject of research, the theoretical analysis of the above criteria, which are a precondition for the introduction of the common euro currency. Emphasis is placed on the empirical analysis of the introduction of the common currency of the Euro into the Republic of Croatia and the advantages and disadvantages of introducing Euro into the Republic of Croatia. The problem of introducing the euro into the Republic of Croatia is external and internal economic imbalances, and weaknesses are manifested in structural uncompetitive and weak performance of the export sector, relatively high export debt, growing fiscal imbalances and relatively high unemployment. The new EU countries, including the Republic of Croatia, encounter various problems in meeting the convergence criteria. Their biggest problems are the overwhelming public debt and the budget deficit caused by the economic crisis in 2008. It can be concluded that the Republic of Croatia meets the criterion of price stability (ie low inflation), stable foreign exchange rate, long-term interest rates and budget deficit (below 3% of GDP), and does not meet the public debt criterion. The Republic of Croatia does not borrow to finance spending and investment but to repay previous debts.