Giessenburg () is a town in the Dutch province of South Holland. It is a part of the municipality of Molenlanden, and lies about 6 km west of Gorinchem.
Giessenburg was a separate municipality between 1957 and 1986. It was created in a merger of the municipalities Giessen-Nieuwkerk and Peursum.
In 2010, the town of Giessenburg had 4889 inhabitants. The built-up area of the town was 0.43 kmò, and contained 911 residences. The statistical area "Giessenburg", which also can include the peripheral parts of the village, as well as the surrounding countryside, has a population of around 2900.