Abstract: The machining process is generally accompanied by intense friction and heat generation, excessive heat flux subsequently leads to thermal damage and shape defects on the workpiece, which will greatly reduce the service life of the tool. As a novel coolant, nanofluid can effectively improve lubrication and cooling conditions in precision machining. In this paper, the ionic liquid 1-ethyl-3-methylimidazole tetrafluoroborate ([EMIm]BF4) was used to disperse the multi-walled carbon nanotubes (MWCNTs) and molybdenum disulfide (MoS2), thereby the nanofluid with excellent tribological properties was prepared. The dispersion and wetting properties of nanofluids were characterized by X-ray diffractometer (XRD), Raman spectrometer, nanoparticle size potential analyzer and contact angle measuring instrument. The thermal properties were tested by thermal conductivity measuring instrument and rheometer. Meanwhile, the friction and wear tester and ultra-depth-of-field microscope were used to analyze the friction properties of nanofluids. The results indicate that MWCNTs and MoS2 nanoparticles modified by [EMIm]BF4 can be effectively dispersed in water, and the laminated structure formed by the adsorption of the two nanoparticles increases the particle size distribution range in the composite nanofluid. The three kinds of nanofluids are regarded as pseudoplastic fluids. The composite nanofluid has the smallest contact angle, the average viscosity and the thermal conductivity in the steady state are 1.49 mPa.s, and 1.19 W?mK-1 (65°C) respectively. In addition, the modified nanoparticles greatly enhance the lubricating performance of the base fluid. Compared with the traditional coolant, the friction coefficient and the volume wear rate of the prepared nanofluids are reduced by 10.75% and 72.33% at the highest.