PURPOSE: To provide a liq. detergent compsn. exhibiting excellent temp. stability and foaming properties and giving excellent feeling in its use, by blending a particular N-acyl amino acid salt and behenyl alcohol in predetermined proportions.

CONSTITUTION: 4-30wt.% at least one N-acyl amino acid salt (A) of the formula (wherein R1 is a 7-21C alkyl or alkenyl; each of M1 and M2 is H, an alkali metal or an alkanolamine; and n is 1-2) (e.g., monotriethanolamine salt of N- lauroylglutamic acid) and 0.2-5wt.% behenyl alcohol (B) are incorporated, thereby producing a liq. detergent compsn. The behenyl alcohol is a 22C straight-chain, satd. monohydric alcohol, and can be produced by various methods including one comprising subjecting a fatty acid, e.g., obtd. from rapeseed oil to hydrogen reduction under a high pressure and performing distillation for purification. The obtd. detergent compsn. can advantageously be used as a shampoo, etc.