Joseph Preston (born June 14, 1955) is a Canadian politician who currently serves as the mayor of St. Thomas. He was previously a member of Parliament, representing Elgin—Middlesex—London riding from 2004 to 2015 as a member of a Conservative Party of Canada. He defeated Liberal incumbent Gar Knutson in the 2004 federal election. He was re-elected in the 2006, 2008 and 2011 federal elections. He did not run again in 2015 and retired from parliament. On July 10, 2018, Preston announced that he was running for mayor of St. Thomas in the 2018 Ontario municipal election, which he won. Prior to being an member of Parliament, he was an entrepreneur in St. Thomas, and was active in local politics.

Electoral record