Sir Douglas Julian Carter KCMG (5 August 1908 – 7 November 1988) was a New Zealand politician of the National Party.
Carter was born at Foxton in 1908, the son of Walter S. Carter. He received his education from Palmerston North and Waitaki Boys' High Schools. Afterwards, he was a farmer and active in various farming organisations. He was chairman of the New Zealand Pig Producers council, and was with the New Zealand Sharemilkers Employers Association, the Waikato Province Dairy Section of Federated Farmers, and was on the Waikato Primary Producers council.
He represented the Raglan electorate from 1957 to 1975, when he retired. He was Minister of Agriculture under Keith Holyoake (1969–1972) and then John Marshall (1972), followed by Minister of Agriculture and Fisheries (New Zealand) (1972). He was Postmaster-General from 1969 to 1972. He retired from Parliament in 1975 and was succeeded by Marilyn Waring.
From 1976 to 1979 he was the High Commissioner to the United Kingdom.
In the 1977 Silver Jubilee and Queen's Birthday Honours, Carter was appointed a Knight Commander of the Order of St Michael and St George, for public services.