Abstract: A new breed of lubricant using CaCO₃ nanoparticles as an additive for PFPE-supramolecular gels (CaCO₃-supramolecular composite) was fabricated successfully. It aimed to solve the problems that nanoparticles with excellent anti-wear and anti-friction performance as additives were insoluble into PFPE oils, which limited the application of nanoparticles in the field of aerospace lubricant. Many researchers have found that gelators self-assembled in the liquid (water, organic solvent, oils) to form complicated 3-D networks that have spatial confinement effect for nanoparticles, which could increase the dispersion stability of CaCO₃ nanoparticles in PFPE oil. Nature precipitation was used to explore the dispersion stability of CaCO₃ nanoparticles with a diameter of 100 nm as a lubricant additive in PFPE-supramolecular gels. The results showed that the network of PFPE-supramolecular gels had good spatial confinement effect for CaCO₃ nanoparticles and it would not self-aggregate even after 3 months. In addition, the thermostability and mechanical strength of PFPE-supramolecular gels were improved due to the excellent thermal and mechanical stability of nanoparticles. The thermostability was evaluated by differential scanning calorimetry (DSC) and (thermal gravimetric analyzer) TG. The results showed that the sol-gel transition temperature of CaCO₃-supramolecular composite and PFPE-supramolecular gels were about 123 ℃, which indicated the CaCO₃ nanoparticles had no effect on the gelation property of PFPE-supramolecular gels. However, the TG results showed that the thermal decomposition temperature of CaCO₃-supramolecular composite (269 ℃) was higher than PFPE-supramolecular gels (260 ℃) due to the participation of CaCO₃ nanoparticles. The rheological property of CaCO₃-supramolecular composite was expressed by rheometer, which showed high shear strength, shear thinning and good creep-recovery properties. The shear strength of CaCO₃- supramolecular composite (180 Pa) was much higher than PFPE-supramolecular gels (56 Pa), which was attributed to the high strength of CaCO₃ nanoparticles. Usually, nanoparticles as lubricant additives significantly improve the tribological property. The fretting friction testing machine (SRV-IV) was used to appraise the tribological properties of CaCO₃-supramolecular composite and PFPE-supramolecular gels, which showed that the CaCO₃ nanoparticles as lubricant additives composite had higher extreme pressure, lower friction efficient and volume of wear scar under a temperature of 120 ℃ and a load of 500 N. The extreme pressure of CaCO₃-supramolecular composite was increased by 550 N compared to PFPE-supramolecular gels. The friction coefficient and volume of wear scar were reduced by 36.90% and 87.36% under a load of 500 N at room temperature with 5.0% (mass fraction) CaCO₃ nanoparticles as additives in PFPE-supramolecular gels. Finally, the lubricating mechanism of CaCO₃-supramolecular composite was characterized by X-ray photoelectron spectrometer. The results showed that the excellent tribological properties of CaCO₃-supramolecular composite were attributed to the shear-film on the worn surface and the self-repairing performance of CaCO₃ nanoparticles. Some of the gelators adsorbed on the worn surface produced lubricant film to avoid its direct contact and reduce wear. And the spherical CaCO₃ nanoparticles as bearings during the sliding process improved the anti-friction and anti-wear properties of CaCO₃-supramolecular composite.