The 39-year-old, who just finished filming "Iron Man 3" with Robert Downey Jr, said she is hesitant to play Pepper in the "Avengers" sequel, reported Aceshowbiz.
"I just came off of 'Iron Man 3', which is as special effect-y and action-y as it gets, so to do something like 'Thanks for Sharing' where it's really small, funny and exciting, is really great.
"I don't know about returning for 'The Avengers 2', I'm getting old for this, you know what I mean?," she said.
Though she might not appear in "The Avengers" sequel, Paltrow will still reprise Pepper Potts in the third armored hero movie, which is set to open in the US on May 3.