Joseph Theodoor "Joep" Leerssen (born 12 June 1955, Leiden) is a Dutch comparatist and cultural historian.
He is professor of European studies at the University of Amsterdam, where he also holds a Royal Netherlands Academy Research Professorship.
In addition, he has held guest professorships and visiting fellowships in Harvard (Erasmus Chair), Cambridge (Magdalene College) and Göttingen.
While emphasizing the agency of culture in the rise and spread of nationalism, he considers this culture to consist of a set of literary myths and stereotypes which only in modern times, under the influence of Romantic historicism, came to be mistaken for long-standing ethnic continuities.
Since nationalism always involves an oppositional dynamics between different societies, and can therefore never be adequately comprehended on a single-country basis, Leerssen pleads for a rigorously transnational, comparative approach.