The latest innovation in modern payment transactions is the emergence of blockchain-based cryptocurrencies. They were created in response to problems which create state currencies; the centrality of the system, the lack of confidence in them, the number of intermediates in payment, causing the increase in costs of fees for payments of goods and services, the inability to convert certain currencies, the mismatch of values for faulty monetary policies and political corruption, and can be considered as an upgrade to the current emergence of electronic money. However, there are certain problems with the legal definition of the cryptocurrencies. Namely, most central banks do not recognize that cryptocurrencies are real money because they do not meet the underlying conditions to be considered money (legal means of exchange, measurement and retention of value), but this does not mean that trading is necessarily illegal (except in some countries) because even some states issue their own form of cryptocurrencies (central bank digital currencies). Therefore, there is a need to define what is actually a cryptocurrency - is it a form of money, property, securitie, capital, or something else. Depending on the national definition of the cryptocurrency, state decides to add it in the tax system - either by incorporating into existing laws or by adopting new legal acts. Also, the cryptocurrency definition decides on the form of taxes by which the cryptocurrency will be taxed (direct or indirect), and the advantages and disadvantages thereof. Although the current volume of cryptocurrency transactions is still considered small, the proper organization of regulation and the consequent interpretation of tax laws give the state the ability to raise funds and make technological progress and develop overall economic activity.