Marcin Piotr Czepelak (born 14 July 1978, Gliwice)[1] is a Polish jurist who serves as a Secretary-General of the Permanent Court of Arbitration, the Hague.

In 2016, he was awarded post-doctoral degree (habilitation) on the basis of his monograph Party autonomy in the EU Private International Law.

[4] He has been participating in research projects at the Max Planck Institute in Hamburg and the University of Cambridge.

[3] He specializes in international civil procedure, the protection of foreign investments and the law of treaties.

[9][10] On 14 February 2022 he started his 5-year term as a Secretary-General of the Permanent Court of Arbitration, the Hague.