The 84-year-old Strictly Come Dancing presenter carried the flame from BBC Television Centre, which marked the site of the White City Stadium, where the Olympics was hosted in 1908.
He also tap-danced for fans, adopted his trademark pose and shook hands with numerous spectators.
After the stint, Forsyth told BBC News: "It's very emotional, it's unexpected, it's wonderful, it's the occasion and everyone is so excited - including me.
"This year has been fantastic for me. I did the Albert Hall, which I never ever dreamed I would do, I did a speech for the all the Lords and Knights of the land and now this - my year has been a most exciting year.
"The crowd were marvellous, you can't beat a big crowd getting excited - it's magnetism. I just can't help having magnetism!"
David Walliams and Absolutely Fabulous stars Jennifer Saunders and Joanna Lumley also took to the streets today to parade the Olympic torch, along with Bollywood actor Amitabh Bachchan and UN Secretary General Ban Ki-Moon.
Earlier this week, EastEnders made history by becoming the first drama series to incorporate live footage of the Olympic torch relay.
Watch some fan-shot footage of Bruce Forsyth's torch relay below: