Peter John Duncan (born 10 July 1965) is a Scottish Conservative Party politician. He was the Member of Parliament (MP) for Galloway and Upper Nithsdale from 2001 to 2005.

Born in Ayrshire, Duncan attended Ardrossan Academy in Ardrossan, North Ayrshire and was educated at the University of Birmingham where he obtained a BCom in 1985. He later worked as a business and communications consultant for Mackays Stores Ltd from 1985 to 1988 in addition to running the family textile business - John Duncan & Son from 1988 to 2000. In September 1997, he appeared as a member of the audience during a Scottish Television debate about the devolution referendum, and spoke opposing the establishment of a Scottish Parliament. Duncan later stood for election to the very parliament he initially opposed.

He was elected to the House of Commons at the 2001 general election, taking the Galloway and Upper Nithsdale seat from the Scottish National Party. This made him the sole Conservative MP for the whole of Scotland and the first Conservative MP from Scotland since 1997. In November 2003 he was appointed Shadow Secretary of State for Scotland by new party leader, Michael Howard and he was later named as Chairman of the Scottish Conservative Party.

His constituency was abolished for the 2005 general election and replaced by Dumfries and Galloway. However he failed to win the seat, losing to Labour's Russell Brown.

In the 2007 local elections, the first to take place under the Single Transferable Vote system, he was one of several new Conservative councillors elected to Dumfries and Galloway council.

He stood as the Conservative candidate for the Dumfries and Galloway seat at the 2010 general election. He was defeated by the incumbent Russell Brown again, with a -3.7% swing against. The following year he stood as the Conservative candidate for Midlothian South, Tweeddale and Lauderdale at the Scottish Parliament election, where he came in fourth place.

He married Lorna Anne and they have a son and daughter and, as of 2007, now lives in Dalbeattie in Dumfries and Galloway.

• Official Website
• Peter Duncan^{[permanent dead link]} - Scottish Conservatives website biography
• BBC Profile 2001