Buelens studied Germanic language and literature at the UFSAL (later KUB) in Brussels and the University of Antwerp. He was a lecturer at the University of Antwerp for several years. In 2005, he was Professor of Dutch Literature at the University of California, Berkeley, and in May of the same year he was appointed Professor of Dutch Literature at Utrecht University. In 2008 he was Kluge Fellow of the Library of Congress (Washington D.C.) and was appointed Extraordinary Professor in the Department of Afrikaans and Dutch at Stellenbosch University.

In 2012 he was elected a member of the Royal Academy of Language and Literature (Ghent, Belgium) and in 2013 a member of the Academia Europaea.

His current research focuses on literature and the environmental and climate crisis, Flemish Congo literature and culture, the writing of national and global literary and cultural histories, and the dynamics between poetry and the art of song since the Romantic period.