The presenter will join previously announced co-hosts Nancy O'Dell, Mark Thompson and Amanda Byram in fronting the official live pre-show to the 63rd Primetime Emmy Awards from 7pm ET/4pm PT on Fox.
Countdown to the Emmys will feature interviews with the night's nominees and attending celebrities on the red carpet ahead of the annual awards ceremony which airs 8pm ET/5pm PT on Fox.
Glee star Jane Lynch will host the main ceremony.
> Emmy Awards 2011 Jane Lynch interview: 'I don't want to make a fool of myself'
> Primetime Emmy Awards 2011 - Nominees
Jones can then be seen on the two-night series premiere of X Factor on Wednesday, September 21 and Thursday, September 22 on Fox.
The new vocal competition will feature judges Simon Cowell, Paula Abdul, LA Reid and Nicole Scherzinger searching for America's next singing superstar. It was open to all individual singers and groups from the age of 12 upwards.
X Factor's winner will secure a $5 million recording contract with Syco/Sony Music and the chance to appear in a Pepsi Super Bowl commercial.
Fox will air an extended eight-minute preview of X Factor following NFL on Fox's late doubleheader match-ups this Sunday featuring previously unseen footage from the record-breaking Los Angeles and Chicago auditions.
> Read Digital Spy's full X Factor headlines
Watch Steve Jones introduce himself to X Factor viewers below: