Disclosed is a pretreatment agent which can achieve a chemical treatment such as the formation of permanent waves or hair-dye uniformly only by pre-treating hair with the pretreatment agent, and which can impart smooth and soft touch to hair as if a hair treatment is applied to the hair after the chemical treatment. Specifically disclosed is a hair treatment composition which is characterized by comprising (A) a tertiary amine, (B) a quaternary ammonium salt and (C) a higher alcohol, wherein the ratio of the content of the higher alcohol to the total content of the tertiary amine and the quaternary ammonium salt is 0.1 to 1.0 by weight and the pH value of the whole composition is 7.0 or higher.