The US blogger famous for his opinions on celebrities, including Paris Hilton, will report from the event backstage and on the red carpet as the stars arrive.
Hilton, whose real name is Mario Lavandeira became famous in early 2005 when his blog was voted "Hollywood's most hated website" by the Insider.
Richard Godfrey, senior vice president and executive producer of the MTV Europe Music Awards, said: "This is an incredible coup as Perez is the pioneer of celebrity exposé blogging.
"As the host of this year's live web broadcast he is sure to bring his own unique style of incisive reportage to the show to make it a web experience to remember."
Hilton said: "I am honoured and thrilled to be involved with the Europe Music Awards. I've watched the show every year from the US, but this will be my first time attending and presenting, so that's especially exciting."
In 2007 the MTV EMAs broadcast on 19 channels across Europe as well as across the US and Asia and reached a total television audience of over 30m people.
MTV EMA websites saw a 35% year-on-year increase in traffic to 3m unique users with total visits on show day, November 1 2007, increasing by 75% compared to 2006.