Kasterlee (Dutch pronunciation: [ˈkɑstərleː]) is a municipality located in the Belgian province of Antwerp. The municipality comprises the towns of Kasterlee proper, Lichtaart and Tielen. On January 1, 2006 Kasterlee had a total population of 17,908. The total area is 71.56 km² which gives a population density of 250 inhabitants per km². The town is twinned with Plaffeien.