Marlen Ibrayev was born in 1978 in Alma-Ata.
In 1999, he graduated from the L.N. Gumilyov Eurasian National University with a degree in Economics and Management, in 2002 he graduated from the Academy of Jurisprudence of the Higher School of Law "Adilet", majoring in Jurisprudence. In 2004, he received a master's degree in European Integration Law at the University of Leipzig.
He started his career in 2002.
In 2002-2006, he worked in the structure of the Ministry of Foreign Affairs of Kazakhstan, in 2006-2007, in Center for International Programs JSC. In 2007-2010, he worked in the banking sector. In 2010-2016, he held the posts of the third secretary of the International Legal Department of the MFA RK, as well as the third, second, first secretary of the Embassy of the Republic of Kazakhstan in the Swiss Confederation.
At the Office of the Prime Minister of the Republic of Kazakhstan, he has worked since 2016. In 2016-2017, he was the Head of the sector of operational information of the Information and Analytical Center of the OPM RK. Since May 2017 — Deputy Head of the IAC of the OPM RK.