Giessen-Nieuwkerk (in Dutch; Flemish pronounced as /ˌɣisəˈniukɛr(ə)k/) is a former town in the Dutch province of South Holland. It is now called Giessenburg. It is also the name of a former municipality, that existed until 1957, when it merged with Peursum to form the new municipality of Giessenburg.
The name means "Giessen-New Church", and refers to the small river Giessen. The town Giessen-Oudekerk ("Giessen-Old Church") is located 2 km southwest.