Abstract: N-oleoylglutamic acid as water-based lubricant additive was prepared by reaction of glutamic acid with oleoyl chlorides,and its structure was characterized by means of IR.Behavior of friction and wear N-oleoylglutamic acid salt with triethanolamine as an additive in water was examined on a four-ball machine.Element composition of the boundary lubricant film was analyzed by means of Auger electron spectroscopy(AES).It was found that the additive considerably increase load-carrying capacity and anti-wear and friction-reducing abilities.It was attributed to the formation of a boundary lubricant film well-bonded on the rubbing steel surface by way of adsorption and tribochemical reaction under heavy load,owing to the polar-group of molecular adsorbed onto the metal surface,and the hydrophobic long chain alkyl formed the absorbed film.The additive also exhibited anti-rust property and antimicrobial property.