Ottignies-Louvain-la-Neuve is a municipality located in the Belgian province of Walloon Brabant. On January 1st, 2004 Ottignies-Louvain-la-Neuve had a total population of 29,208 (14,419 males and 14,789 females). The total area is 32.96 km² which gives a population density of 886.06 inhabitants per km².

There are two main towns in the municipality:

• Ottignies
• Louvain-la-Neuve (sometimes abbreviated as LLN), 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.