The present invention provides an organopolysiloxane having a substituent shown by the following general formula (1), -R1-(NR2-R3-)n-NR4R5 (1)wherein R1 represents a divalent hydrocarbon group having 1 to 10 carbon atoms R2, R4, and R5 each independently represent a hydrogen atom, a monovalent hydrocarbon group having 1 to 10 carbon atoms, a quaternary ammonium salt-containing group shown by the following general formula (2), or a polyoxyalkylene group shown by the following average composition formula (3) R3 represents a divalent hydrocarbon group having 2 to 10 carbon atoms provided that at least one quaternary ammonium salt-containing group shown by the following general formula (2) and at least one polyoxyalkylene group shown by the following average composition formula (3) are contained in one molecule of the organopolysiloxane and "n" is 0 to 3wherein R6 represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 30 carbon atoms "a", "b", and "c" are each independently 0 to 100. This organopolysiloxane can give a hair cosmetic being able to protect hair through the superior adsorptive affinity, to add conditioning effects such as smoothness, easy combing, and softness in a wet condition and in a dry condition, and also able to give gloss in a dry condition.
