The 35-year-old Oscar winner is being recognized for her versatility as an actress and for delighting the MTV audience throughout her career. "Saturday Night Live" star Jason Sudeikis will host Sunday's ceremony, where Ryan Reynolds, Blake Lively, Steve Carell, Shia LaBeouf, Patrick Dempsey, Cameron Diaz, Selena Gomez and Nicki Minaj are among those set to present the prizes.

Fans voted online for the winners in categories such as best kiss, best villain and best line from a movie. MTV chose Witherspoon, who joins previous Generation Award winners Sandra Bullock, Ben Stiller, Adam Sandler, Mike Myers, Tom Cruise and Jim Carrey.