Sir Gerald Alfred Thesiger, MBE (25 December 1902 – 16 April 1981) was a judge of the High Court of England and Wales of the Queen's Bench Division between 1958 and 1978.
He was educated at Gresham's School, Holt, Magdalen College, Oxford (1922–1925), and the Inner Temple.
The British general Frederic Thesiger, 2nd Baron Chelmsford, and the judge Alfred Henry Thesiger (one of the youngest Lords Justices of Appeal in history) were his great-uncles.
During World War II, he was commissioned as a Major in the Office of the Judge Advocate General, and was appointed Recorder of Hastings in 1942.
He became a Bencher of the Inner Temple in 1956 and served as a High Court Judge of the Queen's Bench Division between 1958 and 1978.