The Blue Crush actress and Skarsgård were spotted by X17 Online photographers leaving a showing of Fantastic Mr Fox in Hollywood earlier this week.
When asked about their relationship, she answered: "You guys are funny. Friends, guys! We work together!"
Skarsgård previously told Radar Online that he was "not dating anyone" and joked that the only special women in his life were his "mum and sister".
Bosworth and Skarsgård recently signed on to appear together in a remake of 1971 thriller Straw Dogs, which originally starred Dustin Hoffman and Susan George.