Hatfield is a town in Hertfordshire, England. It is administered together with Welwyn Garden City as the Welwyn Hatfield district of Hertfordshire.

The town is the site of the original campus of Hatfield Polytechnic, which has since become the University of Hertfordshire. It is also the location of the first de Havilland aircraft factory with an associated airfield where airliners such as the Dove, Heron, Comet, Trident and HS146 were built. Production of the latter type was transferred to Woodford in Cheshire during the 1990s by which time it was known as the British Aerospace 146 "Whisperjet". An early bizjet, the DH125, was also developed here although mass production took place at Hawarden in Cheshire. Some components of wind turbines were also developed here prior to the airfield's closure. Parts of the airfield are now in use as film studios.

Until the early 1990s British Aerospace maintained a substantial presence within the town. Their vacated premises and surrounding grounds served as a film set for the night-time scenes of the BBC/HBO television drama Band of Brothers. Subsequently, a large section of the land was purchased by the University of Hertfordshire and the 120 million de Havilland Campus, incorperating a 15 million Sports Village, was built, opening in September 2003. The university has closed its sites at Watford and Hertford, and faculties situated there have been relocated to the de Havilland Campus.

The area contains the site of a fatal GNER train derailment on October 17, 2000. The crash brought track maintenance deficiencies to public attention, to the severe detriment of Railtrack, the company established to manage rail infrastructure, and set in motion the events that led to its insolvency. It is five miles north of Potters Bar, scene of a later fatal train derailment.

A number of places named after Hatfield can be found around the world:

  • Hatfield, Pretoria, South Africa - an affluent suburb on the east side of the city, containing a number of consulates, embassies and the University of Pretoria.
  • Hatfield, Massachusetts, United States of Amrica