Christopher Guerin, aged 12, is a member of Mensa with an IQ of 162, eight points higher than the Countdown queen. The schoolboy from Great Barr, Birmingham, beat thousands of hopefuls to make it on to the ITV1 show, hosted by Vorderman.
He breezed through questions on sport and geography before triumphing with his specialist subject, the life of Thomas Beckett.
Vorderman, 42, who has a degree from Cambridge University, said after the show she was amazed by Christopher's brain power.
"Christopher was a fantastic contestant and just blew us away with his intelligence. It was his great sense of humour that shone on the day and we were all delighted when he took this year's
Last year about eight million viewers tuned in to the show, which was won by Laura Hibbert, from Catterick, North Yorkshire.
Christopher, a pupil at King Edward VI School in Birmingham, said: "I'm really surprised to have won but I'm glad it was me and not another girl."
Despite his brain power the average person's IQ is 100 he insists he is an ordinary boy and prefers following Aston Villa to swotting up on schoolwork.
Christopher's father, Tony moved from Ballyheigue, Co Kerry to Birmingham more than 20 years ago. He works as a manufacturing supervisor in Birmingham.
Christopher's mother, Brigid, from Carndonagh in Donegal is a nurse at the city hospital.