Abstract: A novel nitrogen-containing boric acid ester was synthesized from fatty acid methyl ester to be used as lubricant additive. The synthesized additive was characterized by FT-IR technique and its tribological performance in various base oils, e.g. the effect of friction time and load on PB value and wear scar diameter (WSD), were investigated using a four-ball tester. The morphologies of the worn scars were analyzed by means of scanning electron microscopy and energy dispersive X-ray spectroscopy to study the effect of said novel additive on the compositions and chemical states of the friction surface film．Results showed that this nitrogen-containing boric acid ester additive exhibited excellent extreme pressure anti-wear performance. Boron was detected from the worn surface of tested steel ball, which indicated that a lubricating film containing boron was formed on the friction surface by physical adsorption and chemical reaction, resulting in an enhancement of extreme pressure anti-wear function.