It is intended to provide an artificial hair (1) having a heat deformability when heated with a hair dryer or the like to be used in hair styling and a wig using this artificial hair (1). The artificial hair (1) is produced by melting a semi-aromatic polyamide resin having a glass transition temperature of 60<SUP>o</SUP>C to 120<SUP>o</SUP>C together with a resin being non-expandable within the temperature range at a definite ratio. The artificial hair may have a sheath/core structure consisting of a core part and a sheath part covering the core part. As the resin being non-expandable within the temperature range as defined above, it is possibleto use polyethylene terephthalate or the like. As the sheath, it is possible to use nylon 6 or nylon 66. When heated with a hair dryer or the like to be used in hair styling, this artificial hair (1) is heat-deformed and it can retain the shape at room temperature or after washing with a shampoo.
