Gordon Thomson was born on March 2, 1945 in Ottawa, Canada. He studied acting at McGill University in Montreal, and apprenticed at the renowned Stratford Shakespeare Festival in Ontario. After graduating with honors, he appeared on stage in such productions as Godspell, The Imaginary Invalid and A Month in the Country.

Gordon's participation in the ABC Talent Development Program, and a subsequent stint on the daytime series Ryan's Hope, led to his role as the nasty Adam Carrington on the successful primetime serial Dynasty. He also played that same role on the Dynasty spin-off The Colbys. In 1988, his work on Dynasty earned him a Golden Globe Award nomination.

After seven seasons on Dynasty and the show's departure, Gordon returned to daytime soaps. He joined the cast of Santa Barbara in 1990 and remained with the show until its cancellation. He also appeared on The Young and the Restless, Sunset Beach, Passions and Days of Our Lives.

Gordon had guest spots on numerous shows, including Murder She Wrote, Finder of Lost Loves, Silk Stalkings, The Nanny and Beverly Hills, 90210. He had minor roles in the 2006 feature films Poseidon and Little Miss Sunshine.