Ottignies-Louvain-la-Neuve is a Walloon municipality located in the Belgian province of Walloon Brabant. On January 1, 2006 Ottignies-Louvain-la-Neuve had a total population of 29,521. The total area is 32.96 km² which gives a population density of 896 inhabitants per km².
The two main towns in the municipality are Ottignies and Louvain-la-Neuve (sometimes abbreviated as "LLN"). The latter is a new town developed from 1968 in order to provide a home for the Université catholique de Louvain, the French-speaking part of the former Université de Louvain on its separation from the Dutch-speaking part, which remained in the ancient city of Leuven.