Dereham, also known as East Dereham, is a town in Norfolk, England. It lies on the site of a monastery founded by Saint Withburga in the seventh century. A holy well in the town supposedly began to flow when her body was moved from the town to Ely.

Notable buildings in the town include the pargetted Bishop Bonners Cottage, built in 1502, the Norman parish church, a windmill and a large mushroom-shaped water tower. The town is also home to a museum of rural life.

Famous people from the town include Brian Aldiss. It is also known as the place where William Cowper died.