The “European tax law” is a set of regulations issued by the EU institutions and designed to provide the control of tax matters over the tax legislations of the Member States. However, the existence of EU rules aimed to regulate the procedures for taxation in the European Member States is not enough to identify an area of an independent and autonomous law. In fact, if the tendency to profile the EU law is developing in the recent times, in order to valorise the regulatory provisions of specific areas of the legal system (giving a meaning to the definition of “European private law”, or “European administrative law” or even “European trial law”), it must be considered that the identification of an autonomous sector of law requires the logic of a “legal system”; it basically implies the existence of principles and juridical values and the dynamic relationships between the norms. Therefore, the existence of a set of general rules by EU institutions cannot be considered sufficient to identify a “European tax law”; if these rules compose a mere aggregate without a functional meaning, the element of the systematic unity would lack and there should not be an autonomous order of law.