The 22-year-old model, who has not been named, alleges that she met 52-year-old Copperfield when he appeared at a show in Kennewick in January 2007, according to the Seattle Times.
The woman claims the magician invited her to his island where she was sexually assaulted.
The model filed her case against Copperfield, whose real name is David Seth Kotkin, in court on 29 July.
Copperfield is famous for incredible magical feats and illusions such as appearing to walk through the Great Wall of China and causing the Statue of Liberty to vanish.
