Abstract: A permanent wave treatment method is provided in which the difference between wet and dry wave shape is small. A first permanent wave agent is applied to swell and soften hair wound around a rod, the first permanent wave agent is rinsed off, a chemical agent spray member 42 is moved back and forth inside a hood 2 while uniformly spraying the entire hair with a chemical agent comprising an intermediate treatment agent that contains ascorbic acid salt; while heating with a blower 12, the ascorbic acid salt is adhered to the hair wound around the rod, and the moisture is maintained.