This dissertation analyses the application of the principle of non-refoulement to the cases of expulsion of foreigners, with a focus on the pushback of foreigners. The first part analyses the gen- eral issues related to the regulation of the legal status of foreigners and their expulsion. Mandatory and soft law requirements for the expulsion of foreigners adopted in the framework of the United Nations, Council of Europe and European Union are analysed. The second part of the research analyses the impossibility of expulsion of foreigners in the light of the principle of non-refoulement. This part of the dissertation highlights the content of the non-refoulement principle and its relation- ship with asylum law. The third part of the dissertation focuses on the practice of pushback and its compatibility with the principle of non-refoulement. This part analyses ECHR legal regulation and ECtHR’s case law as well as the EU legal regulation and the case law of the CJEU, on the basis of which the tests of assessment are established. Based on the established tests of the ECHR legal framework and the EU legal framework, the Lithuanian legal framework and practice are analysed and evaluated. This assessment is carried out in two aspects: rejection at the border and the access to asylum procedure.