In only one decade, cryptocurrencies have witnessed significant growth, with Bitcoin being the most dominant one. They are not efficient payment methods, although they bring some benefits linked to the underlying technology they use (Blockchain). In reality, they function more as investment assets than as payment instruments and pose various risks, which are very similar to those encountered on capital markets (price volatility, fraud, market manipulation). In order to deal with these risks, regulation should apply to intermediaries who provide services in relation to cryptocurrencies, such as crypto wallets, operation of crypto exchanges and brokerage. To this end, the European legislator should consider two options. It could, on the one hand, bring cryptocurrency service providers within the scope of the existing financial services regime and thus modify MIFID II in order to include cryptocurrencies in the list of financial instruments. The European legislator could also, on the other hand, aim at creating a new appropriate and proportionate regime that draws on the existing one. Insofar as the existing regulatory framework was not designed with cryptocurrencies in mind and as some of the current rules may not be tailored to the specificities of these assets, the second option is preferable.