Abstract: The tribological properties of imidazoline borates as additive in water were evaluated using a four ball test machine at different additive concentration and load.The rubbed surfaces were investigated using X ray photoelectron spectroscopy. The tribological test results showed the imidazoline borates have good lubricating performance and load carrying capacity.Imidazoline borates reacted with the metal surface in friction process and produced a complex film composed of organic imidazolines and partially decomposed products which contributed to the good lubrication and antiwear properties.