Graaff-Reinet is a town in the Eastern Cape Province of South Africa. It is the oldest town in the province. It is also the sixth-oldest town in South Africa, after Cape Town, Stellenbosch, Simon's Town, Paarl and Swellendam. The town was the centre of a short-lived republic in the late 18th century. The town was a starting point for Great Trek groups led by Gerrit Maritz and Piet Retief and furnished large numbers of the Voortrekkers in 1835–1842.

Graaff-Reinet is home to more national monuments than any other town or city in South Africa. It is also known for being a flourishing market for agricultural produce, noted for its mohair industry, and sheep and ostrich farming.