The move has sparked several changes at the top, with executive chairman Sir Robert Horton and non-executive directors Justin Dowley and Nick Irens resigning their positions with immediate effect. Also Tim Bunting from Goldman Sachs has joined the board and taken over as chairman of the company.
Yu, who has a background in computer science, was formerly CTO and then COO at Betfair before this week's boardroom reshuffle and is seen as something of a surprise appointment by outsiders.
But Betfair co-founder Edward Wray said in a statement: "We would like to thank Bob, Nick and Justin for their valuable contribution to Betfair, which continues to go from strength to strength. We're delighted that David steps up to the leading role in the company."
In an interview with ZDNet Australia's sister site Silicon.com last year before his appointment, Yu said: "I think the secret of my success here has been hiring people who are smarter than me, who know their areas a lot better than I do and you hire them and they just get on with it, and it's really easy. All I do is walk around and try not to bother them."
Betfair made an operating profit of £20 million (AU$47 million) last year and the company said it remains on course to hit "aggressive" targets for this financial year-end in May.
Silicon.com's Andy McCue reported from London. For more coverage from Silicon.com, click here.
