Born in Bree in 1959, Marleen Vaesen studied applied economics at the KU Leuven, before going on to achieve an MBA at the University of Chicago in the United States.

In 1982, she joined Procter & Gamble, initially as director of marketing for Belgium. In 1995, she became Director of Marketing for Western Europe. In 1999, she joined Sara Lee and Douwe Egberts, becoming Senior Vice President in 2004. At Douwe Egberts, Vaesen oversaw the introduction of coffee pods across Europe. In 2012, she became CEO of fruit and veg company Greenyard, where she was succeeded by Hein Deprez in January 2018. In December 2018, she became CEO of lingerie company Van de Velde, where she served as a board member from 2012-2022.

Vaesen has also been a director at cinema chain Kinepolis since 2018, as well as at investment company De Eik, MRBB, Arvesta and Dutch dairy group FrieslandCampina since 2019.