To provide a permanent wave treatment for hair in which all of the treatment form, the resiliency of curl, the gloss of hair, the runability of a comb, or the like are good, and there is no possibility of an allergic reaction.

The reducing treatment of hair is first carried out by alkaline for a short period of time, and then is carried out by acid for a long period of time. In other words, a) hair is wound around a curler, b) an alkaline permanent treating agent making a base of a hair keratin reducing substance is provided, c) acted for 7 to 10 minutes at room temperature (2 to 6 minutes under a heating temperature), d) it is treated by using an acid aquatic intermediate cleaning agent of 50 to 2000 ml of pH = 2 to 6.8 in which an aliphatic organic acid, hair protective and conditioning compounds, and at least water of 50% by weight are included, as it is without previously washing with water, e) if necessary, surplus liquid is wiped away, f) the intermediate cleaning agent is acted at room temperature for 10 to 30 minites (for 5 to 15 minutes under a heating temperature) (this time is made at least two times of the process c)), g) if necessary, water washing is carried out, h) it is treated by a fixative, and i) the fixative is washed away with water or shampoo.