Oud-Beijerland is a town and former municipality located in the western Netherlands within the province of South Holland. It currently serves as part of the Hoeksche Waard municipality.
The town is situated adjacent to the confluence of the Oude Maas and Spui rivers. As of 2020, Oud-Beijerland had a population of 24,575, making it the most populous town on the island of Hoeksche Waard.