To obtain a cosmetic composition which gives the hair no greasy feeling and excellent combing and conditioning effect and gives the skin excellent sense of use by using a specific basic amino acid derivative and an amphoteric surfactant.

This cosmetic contains (A) 0.01-10 wt.% of one or more kinds of basic amino acid derivative represented by formula I [R1 is a 8-22C alkyl or alkenyl; j is 0 or 1; X is H or a substituent of formula II (R2 is same as R1; n is 0 or 1); k is 0-5 and, when k is 0, Y is a substituent represented by the formula: -(CH2)m-Z (m is 1-5; Z is -NH2 or the like); when k is 1-5, Y is an amino group] and salts thereof, and (B) 0.01-50 wt.% of one or more selected from amphoteric surfactants. The compound of formula I is prepared by reaction of a basic amino acid with a glycidyl ether or an epoxy alkane.