The 29-year-old, who played the glamourous Kelly Windsor between 1993 and 2000 before reprising the role in 2005 until 2007, will make her comeback to the show following a stint searching for acting work in Los Angeles.
Silva told the Daily Mail: "I absolutely loved playing Kelly. She's going to be three years older but probably not three years wiser! Whenever Kelly is around she's always caught up in something which makes her a lot of fun.
"I'm really looking forward to working with the new, talented cast as well as catching up with old friends. The chance to come back was just too good an opportunity to turn down."
Kelly was last seen splitting up with Nick Miles's Jimmy after he found out that she had aborted their unborn child in order to sign a modelling deal. It is expected that Kelly's return will come at a cost for Jimmy, now living with his wife Nicola and daughter Angelica.
Emmerdale's series producer Gavin Blyth added: "Kelly is as manipulative and destructive as ever and there will be no going back from the damage she looks set to cause to Jimmy. The story will ensure an explosive start to 2011 for Emmerdale."