The funnyman was in the stands at London's Wembley Stadium to see Crystal Palace play Watford in a key game to decide which club would win promotion from Britain's Championship division to the Premier League.
Sir Elton, who serves as honorary life president of Watford Football Club, was also at the match with his partner David Furnish and two-year-old son Zachary, and both stars were on the edge of their seats as the game went to extra time.
However, Crystal Palace proved victorious with a late goal - and Izzard was thrilled with the result.
In a post on his Twitter.com page, he writes, "Crikey, we won! Crystal Palace are through to the Premier League at Wembley."