The actress is currently dating Somerhalder and also appears alongside him in The Vampire Diaries.
Dobrev, who told MTV News that she has not yet read Fifty Shades of Grey, explained that she will "have to see" whether she is offered a role in the movie but said that she does not want to be in the movie with Somerhalder.
"I don't know if that's a good idea," she said. "I think it's best for any of the actors on The Vampire Diaries to kind of do their own things... and create new characters... They'll see me as Elena and they'll see him as Damon if we do a film together."
Dobrev also suggested that Somerhalder, who has said that he "would be up for" a part in Fifty Shades of Grey, is more suited to the movie.
"I think it would be better [if] either he should get it or I should get it," Dobrev said. "I know that apparently he's really great for the role, so I hope that he gets it."
Robert Pattinson, Alexander Skarsgård and Chris Pine have also been linked to roles in the Fifty Shades of Grey movie.
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