Thomas David Burnett (25 November 1877 – 30 November 1941) was a New Zealand politician of the Reform Party, and joined the National Party after the 1935 election.
Burnett's parents were Andrew Burnett and Catherine Burnett from Strathnaver in the Scottish Highlands, with the locality named after the river of the same name. His parents arrived in Canterbury, New Zealand in 1861 and proceeded to the Mackenzie Basin. In May 1864, they selected the Mount Cook Station, so named after the adjacent mountain, and developed it into a sheep station.
Burnett was born on 25 November 1877, according to the contemporary advertisement, at the "residence" of the Burnetts. Later sources record his place of birth as Timaru or Cave (some 23 kilometres or 14 miles north-west of Timaru), The Burnetts had eight children and to provide better access to education, they purchased land in Cave in 1873 and built a homestead there. To be even closer to the schools in Timaru, Andrew Burnett had a home built in Timaru's Perth Street in 1876; this house became the South Canterbury Museum after Thomas Burnett's death.
Burnett received his education at Timaru Main Primary and Timaru Boys' High School.
Upon leaving school, Burnett worked on Mount Cook Station, which he inherited on his father's death in 1927. In late 2015, the property was for the first time put up for sale, after 151 years in family ownership.
Burnett was for some years a member of the Mackenzie County Council. In the 1919 election, he challenged Charles Talbot of the Liberal Party, the incumbent in the Temuka electorate. Burnett was successful, with a narrow majority of 31 votes, a 0.47% margin.