Derek Coates Barber, Baron Barber of Tewkesbury (b.17 June 1918) is a British member of the House of Lords and was a senior civil servant and agricultural expert.

Barber was educated at the Royal Agricultural College and served in the Second World War. He worked as a farmer in Gloucestershire before serving in various posts at the Ministry of Agriculture, Fisheries and Food 1946-72. Since then he has taken various advisory roles on countryside and agricultural matters, including to the government and BBC.

He has served as Chairman and later President of the Royal Society for the Protection of Birds; President of the Gloucestershire Naturalists' Society; President of the Royal Agricultural Society of England ; and President of the British Pig Association.

Barber was knighted in 1984 and made a life peer as Baron Barber of Tewkesbury, of Gotherington in the County of Gloucestershire in 1992. He sits as a crossbencher.