Piers John Shirley Dixon (29 December 1928 – 24 March 2017) was a British Conservative Party politician.
Dixon was educated at Eton College, Magdalene College, Cambridge, and Harvard Business School. He worked as a stockbroker.
Dixon contested Brixton at the 1966 general election. A member until the close of 1971 of the Conservative Monday Club, he was elected Member of Parliament (MP) for Truro in 1970. He was re-elected in February 1974, but lost the seat to the Liberal David Penhaligon in the October 1974 general election, by 464 votes (0.8%). No Conservative MP represented Truro after Dixon's defeat until Sarah Newton regained the seat from the Liberal Democrats in 2010. Alan Clark noted Dixon in his 1983–1992 diaries, writing "when (the Liberals) get stuck in, really stuck in, they are devilish hard to dislodge".
Dixon married four times. His first wife was the sculptor Edwina Sandys, a daughter of Duncan Sandys and Diana Churchill. They had two sons, Mark and Hugo. The second was Janet, Countess of Cowley. In 1984, Dixon married Anne Olivia Cronin, daughter of John Desmond Cronin, former Labour MP; they had one son, Piers Alexander Jago. In 1994, he married Ann Mavroleon, daughter of John Davenport.