The current increased influx of immigrants from third countries, often illegally entering the territory of the Member States of the European Union, causes many significant problems. This phenomenon is directly affecting the interests of European states in the sphere of their economic, political and security interests. Last but not least, important legal questions also emerge. It is clear, that the rules adopted on the level of European Union law which aim to regulate immigration to the European Union, are vague and uncertain. The question is for example whether the European Union really does have competence to adopt a measure that would set exact numbers of immigrants which must be accepted by each Member States. Questionable is also the mechanism of decision making in the EU institutions and the choice of instruments in which such measures should be adopted. The aim of this paper is to find the answers based on relevant provisions of the Treaty on European Union (hereinafter „TEU“) and the Treaty on the Functioning of the European Union (hereinafter „TFEU“).