Rozenburg is a town and former municipality in the western Netherlands, in the province of South Holland. The municipality had a population of 13,173 in 2004, and covers an area of 6.50 km². It was the second-smallest municipality in the Netherlands in area. On 10 July 2008, the local council decided to disband the municipality and to form a submunicipality of Rotterdam. This was ratified on 27 October 2008 by the Eerste Kamer, and came into effect on 18 March 2010.
The town is located on the former island by the same name: Rozenburg Island. Its current form was created out of three separate parts: Rozenburg proper, the sand bar Welplaat, and the southernmost part of the Hook of Holland. The island is now connected to Voorne-Putten by a sea barrier and a dam.