It is an important concern to explore the pro- perties and principles of lubrication at nano or molecular scale. For a long time, measurement apparatus for film thickness of thin film lubrication (TFL) at nano scale have been devised on the basis of superthin interferometry tech- nique. Many experiments were carried out to study the lu- brication principles of TFL by taking advantages of afore- mentioned techniques, in an attempt to unveil the mechanism of TFL. Comprehensive experiments were conducted to ex- plore the distinctive characteristics of TFL. Results show that TFL is a distinctive lubrication state other than any known lubrication ones, and serves as a bridge between elastohy- drodynamic lubrication (EHL) and boundary lubrication (BL). Two main influence factors of TFL are the solid surface effects and the molecular properties of the lubricant, whose combination effects result in alignment of liquid molecules near the solid surfaces and subsequently lubrication with ordered film emerged. Results of theoretical analysis consid- ering microstructure are consistent with experimental out- comes, thus validating the proposed mechanism. It is an important concern to explore the pro- perties and principles of lubrication at nano or molecular scale. For a long time, measurement apparatus for film thickness of thin film lubrication (TFL) at nano scale have been devised on the basis of superthin interferometry tech- nique. Many experiments were carried out to study the lu- brication principles of TFL by taking advantages of afore- mentioned techniques, in an attempt to unveil the mechanism of TFL. Comprehensive experiments were conducted to ex- plore the distinctive characteristics of TFL . Results show that TFL is a distinctive lubrication state other than any known lubrication ones, and serves as a bridge between elastohy- drodynamic lubrication (EHL) and boundary lubrication (BL). Two main influence factors of TFL are the solid surface effects and the molecular properties of the lubricant, whose combination effects result in alignment of liquid molecules near the solid surfaces and following lubrication with ordered film emerged. Results of theoretical analysis consid- ering microstructure are consistent with experimental out- comes, thus validating the proposed mechanism.