Gordon Thomas (born 1933) is a Welsh author who has written more than fifty books.
Thomas was born in Wales, in a cemetery keeper's cottage where his grandmother lived. He had his first story published at nine years old in a Boy's Own Paper competition. With his father in the RAF, he traveled widely and was educated at the Cairo High School, the Maritz Brothers (in Port Elizabeth, South Africa) and, lastly, at Bedford Modern School. His first book, completed at the age of seventeen, is the story of a British spy in Russia during World War II, titled Descent Into Danger. He refused the offer of a job at a university in order to accompany a traveling fair for a year: he used those experiences for his novel, Bed of Nails. Since then his books have been published worldwide. He has been a foreign correspondent beginning with the Suez Crisis and ending with the first Gulf War. He was a BBC writer/producer for three flagship BBC programmes: Man Alive, Tomorrow's World and Horizon.

He is a regular contributor to Facta, the respected monthly Japanese news magazine, and he lectures widely on the secret world of intelligence. He also provides expert analysis on intelligence for US and European television and radio programs.His book Gideon's Spies: Mossad's Secret Warriors became a major documentary for Channel Four that he wrote and narrated: The Spy Machine. It followed three years of research during which he was given unprecedented access to Mossad’s main personnel. The documentary was co-produced by Open Media and Israfilm.

Gideon's Spies: Mossad's Secret Warriors has so far been published in 16 languages. A source for this book was Ari Ben-Menashe, a former Israeli intelligence agent, and legendary Israeli spy Rafi Eitan. According to Charles Foster in Contemporary Review: "Writers who know their place are few and far between: fortunately Mr Thomas is one of them. By keeping to his place as a tremendous storyteller without a preacher's pretensions, he has put his book amongst the important chronicles of the state of Israel."