Thomas Edward "Tom" Siddon, PC (born November 9, 1941) is a Canadian politician.
Born in Drumheller, Alberta, Siddon pursued engineering, graduating with distinction from the University of Alberta in 1963, winning the Gold Medal in Mechanical Engineering, followed by earning his Masters and Doctorate in aeroacoustics from the University of Toronto, Institute of Aerospace. He became a professor at the University of British Columbia and founded a successful aero-acoustics firm, Siddon-Harford & Associates.
After serving as City Councillor in Richmond, BC for two years, he was first elected to parliament in a 1978 election as a Progressive Conservative Member of Parliament (MP) to represent the British Columbia riding of Burnaby—Richmond—Delta. He was successively elected in five federal elections between 1978 and 1993, and worked under several Prime Ministers.
When Brian Mulroney became leader of the PC Party, Siddon was appointed the party's science critic in the shadow cabinet. After the Tories won the 1984 election, he was given the cabinet post of Secretary of State for Science and Technology. Siddon proved to be a hard working and competent MP, and was promoted to the Minister of Fisheries and Oceans position on November 21, 1985, in the wake of the tunagate scandal that had forced the resignation of previous minister, John Fraser.