Listen to iHeartRadio Music Festival '14 Radio on iHeartRadio

iHeartRadio Music Festival '14 Radio

The 2014 iHeartRadio Music Festival goes down in Las Vegas this weekend - and it just got a whole lot more star-studded! In addition to the incredible lineup and host Ryan Seacrest, there will be lots of star power in the building as presenters and guests for the show.

Celebrity attendees Fergie, Hilary Duff, Nick Jonas, actor Jamie Foxx, actor Chris Pratt, actor Craig Robinson, Johnny Galecki of "Big Bang Theory," actress Sophia Bush, "Orange is the New Black," stars Taryn Manning, Laverne Cox, Pablo Schreiber and Dascha Polanco, Cecily Strong of "Saturday Night Live," actor Adam Devine, actress Janel Parrish, actor Randy Couture and Karina Smirnoff and Val Chmerkovskiy of "Dancing with the Stars."

Guest presenters from The CW series include Gina Rodriguez of "Jane The Virgin," Colton Haynes of "Arrow," Phoebe Tonkin of "The Originals" and Adelaide Kane of "Reign." Clear Channel's own Elvis Duran, Ellen K, Nikki Sixx, Bobby Bones, Amy Brown, The Breakfast Club, Kane, Romeo, Nessa, Cody Alan, Johnjay and Rich, Mario Lopez, Jenn Marino and more will also make special guest appearances.

The 4th annual iHeartRadio Music Festival takes place Friday and Saturday, September 19th and 20th at the MGM Grand Garden Arena in Las Vegas. The show will be broadcast live on more than 150 iHeartMedia radio stations across the country and will video stream live exclusively on Yahoo Live at for fans nationwide that cannot attend.

Don't miss any of the action - find out how to watch or listen to the iHeartRadio Music Festival live HERE.