Frogmore Paper Mill is a working paper mill situated in Apsley, Hertfordshire, near Hemel Hempstead. The mill is on an island in the River Gade, which forms part of the Grand Union Canal. It is the oldest mechanical paper mill in the world.

The mill was founded in 1690 by Thomas Lombe, who was granted a patent for a new type of papermaking machine. The machine used water power to drive the rollers that pressed the pulp into sheets of paper. This was a significant improvement over the previous method of papermaking, which was done by hand.

Frogmore Paper Mill was one of the most important paper mills in England during the 18th and 19th centuries. It supplied paper to the Royal Household and to many of the leading printers and publishers in the country. The mill also produced a variety of specialty papers, such as banknotes and playing cards.

The mill continued to operate until 1982, when it was closed due to financial difficulties. It was later acquired by The Apsley Paper Trail, a charitable organization, and reopened as a visitor, education and community use center.

In the meantime, the mill is still operating as a papermaking business. The mill also offers workshops and courses on papermaking.

According to the Internet