Disclosed is a fiber for artificial hairs that is given a predetermined shape, the fiber being formed from a synthetic fibroin fiber containing a modified fibroin, and the fiber expanding when placed in a wet state and contracting when dried from a wet state. Also disclosed is a method for producing a fiber for artificial hairs that is given a predetermined shape, the method including retaining a fibroin fiber containing a modified fibroin in a state conforming to a predetermined shape. A wetted fibroin fiber may also be heated while being retained in a state conforming to a predetermined shape.
展开▼