Grimbergen is a municipality located in the province of Flemish Brabant within the Flanders region of Belgium. Situated approximately 10 km (6.2 mi) north of the capital city, Brussels, the municipality covers a total area of 38.61 km² (14.91 sq mi).
The municipality is composed of the towns of Beigem, Grimbergen, Humbeek, and Strombeek-Bever. As of 2017, the population was recorded at 37,030, resulting in a population density of 959 per km² (2,480 per sq mi).