Dr. Milan Brglez was born on 1 September 1967 in Celje. Until the beginning of his university studies at the Faculty of Social Sciences, he lived in Zreče, and since then in Ljubljana. Now he lives in Logatec with his family. 

In 1986, he graduated from the Secondary School of Social Sciences in Celje (Kajuh's Gymnasium), and in 1992 he finished his university degree in Political Science at the Faculty of Social Sciences of the University of Ljubljana, majoring in International Relations. He received the Faculty's Prešeren Prize for his Bachelor thesis "Immunities and Privileges in Modern Diplomatic and Consular Law: An Attempt at a Comparative Analysis" (mentor Prof. Dr. Bojko Bučar). In the academic year 1992/93, he enrolled in a postgraduate master's study of international law at the Faculty of Law of the University of Ljubljana, where in 1996 he successfully defended his master's thesis entitled "Codification of Contemporary Diplomatic Law" (mentor Prof. Dr. Borut Bohte). He received the Zore Prize for his scientific master's thesis. In 2006, he successfully defended his doctoral dissertation entitled "The Importance of Non-positivist Epistemological and Realist Ontological Assumptions for Theorizing and Methodologies of International Relations" (mentor Prof. emeritus Dr. Vlado Benko). He received the award for the best doctoral thesis at the Faculty of Social Sciences in 2007.

From 1 December 1992 till 13 July 2014, he was employed at the Faculty of Social Sciences of the University of Ljubljana. First, he was a Young Researcher at the Center of International Relations, and from 1 December 1999 he worked at the faculty as University Assistant in the courses: Current Problems of the International Community, Diplomatic and Consular Relations, International Relations, and Politics of International Law. In February 2007, he obtained his habilitation, which he still maintains, as an Assistant Professor in International Relations (teaching Diplomatic and Consular Relations, European Protection of Human Rights, Politics of International Law, Politics of the Law of Armed Conflicts and Theories of International Relations). He was a mentor or co-mentor of more than a hundred graduates, many scientific and Bologna master's degrees at home (at the Faculty of Social Sciences and the Faculty of Law of the University of Ljubljana) and abroad (University of Bologna - Forlì and University of Venice), and eight doctoral dissertations. From 2008 to 2014, he was a head of the Chair of International Relations at the Faculty of Social Sciences of the University of Ljubljana.

At the parliamentary elections of 2014, he was elected as a member of parliament and became the president of the National Assembly, and in 2018 he was re-elected as a member of the National Assembly. In 2019 elections he was elected as a member of the European Parliament. He held that position until 16 July 2024.

Dr. Milan Brglez is an author and co-author of numerous professional and scientific works and a member of several domestic and international professional associations. He was also president of the Slovenian Political Science Association, vice president of the Slovenian Red Cross and president of the Slovenian Chess Federation.